Castile EU5 Guide - From Iberian Kingdom to Spanish Empire
Master Europa Universalis 5 with Castile, the ultimate beginner nation. This comprehensive guide covers crown power systems, vassal swarm strategies, personal unions, and the path to Spanish dominance.
Why Castile?
Castile really is one of the best nations to learn Europa Universalis 5
Castile starts with 5.44 million population, mostly Castilian and Catalan, with 95% Catholic faith. The nation offers a perfect blend of military strength, economic potential, and clear expansion paths that make it ideal for learning EU5's complex mechanics.
Secure Starting Position
Control most of Iberia with clear expansion targets and natural defensive borders
Vassal Swarm Strategy
Create multiple small vassals that handle integration automatically
Colonial Superpower
Perfect position for exploring and colonizing the New World
Strong Economic Base
Rich provinces, multiple trade nodes, and unique buildings
Starting Situation & Opening Setup (1337)
Game Setup
Critical First Month Actions
These decisions set up your entire campaign
Cabinet Members (Only 2!)
Unlike most great powers with 3 cabinet members, Castile starts with only 2. This makes your assignments crucial.
Both members assign to:
- Stability Investment (rush to 100 stability)
- Monthly Legitimacy (rush to 100 legitimacy)
Why? 100 stability doubles population promotion speed. 100 legitimacy gives +10% crown power.
Government Reform
Change from Feudal Nobility to Autocracy immediately. Takes ~2 years to implement (completes June 22, 1339).
Fort Management
Rule: Keep only forts in provincial capitals (silver outline on map).
Delete these forts:
- Écija (Sevilla capital has fort)
- Medina del Campo (Valladolid capital has fort)
If an enemy sieges a capital, the entire province falls. Non-capital forts don't protect the province.
Army Setup
Estate Privileges
Revoke "Communal Lands" from peasantry (costs 33 stability but removes 0.20 decentralization push)
Auto-assign taxation for all 4 main estates
Start minting gold (up to -0.00 ducats/month for ~5 ducats extra income)
Core Economic Systems
Markets & Trade Routes
Castile starts with three markets: Burgos (19 capacity), Sevilla (15.5 capacity), and partial coverage in Lisbon.
Two Approaches:
- Beginner: Use Economy → Trading tab and select suggested trade routes for profit
- Advanced: Manually review each market by price and fulfill population needs
Pro Tip:
Automate trade initially, then optimize manually once you understand goods demand. Check markets monthly for gold availability—it's scarce but crucial for minting.
Road Network Priority
Roads are your most important infrastructure investment.
Proximity cost -20% (dramatically increases control)
Improved market access between provinces
Movement cost reduction for armies
Strategy: Build roads in EVERY province before investing heavily in other infrastructure.
Start from capital and work outward. Average control jumps from 16-20% to 70%+ around capital with complete road network.
Building Priority Order
Maximize your economic snowball
Detailed Building Strategy:
Marketplaces (Priority #1)
- • Hold Shift + Click to build max possible in a market region
- • Prioritize capital first (max out 4 marketplaces in Valladolid)
- • Then spread to other provinces (1 per province minimum)
- • Increases trade capacity for more trade routes
Roads (Priority #2)
- • Build systematically from capital outward
- • Creates blue road lines connecting provinces on map
- • Each connection reduces proximity cost by 20%
- • Essential for reaching 70%+ control in all provinces
Special Buildings
- • Royal Court: +10% crown power (build in capital ASAP)
- • Royal Gardens: Additional crown power (needs gold in market)
- • Royal Audience: +max literacy, institution growth, -unrest
RGO Expansion Strategy
Grow your tax base through resource production
Step 1: Identify Market Shortages
Navigate to Economy → Market → Demand tab to see what goods are in shortage.
Example from transcript:
- • Burgos market: Fruit shortages, grain shortages, rice shortages
- • Southern provinces: Lumber in high demand
- • Everywhere: Gold scarce but crucial for minting
Step 2: Build Lumber Mills First
Step 3: Build High-Demand RGOs
Use Production tab → Buildings → Filter by profit to see best options
- • Fruit: Build in Medina del Campo (2+ ducats profit each)
- • Lumber: Build in southern provinces first
- • Grain/Food: Excess food = selling for ducats
- • Gold: Check markets monthly—snipe when available
Step 4: Shift + Click for Efficiency
Advanced Technique: Go to RGO expander, hold Shift + Left Click to build as many buildings as possible up until you run out of money. The most profitable ones are prioritized automatically.
Economy Slider Management
F2 Economy tab optimization
Set to MAXIMUM:
Court Support
Need stability fast—rush to 100
Stability Cost
Doubles pop promotion speed at 100 stability
Set to MINIMUM:
Diplomatic Spending
No subjects initially, save the ducats
Army Maintenance
Small 250-man army, leverage levies early
Result: Should net you 10-20 extra ducats/month for building investments. Every ducat invested in marketplaces and roads compounds your income exponentially.
Values, Parliament & Laws
Centralization Push
Goal: Reach 100 centralization for +50% crown power and -10% proximity cost
Starting Problem:
You start pushing toward decentralization due to estate privileges, especially "Communal Lands" (-0.20 decentralization).
Solution:
- Revoke Communal Lands immediately (costs 33 stability)
- Use Parliament debates like "Expand Gravel Road Network" (+10 centralization)
- Assign cabinet members to push centralization
- Change laws through Parliament
Parliament System
How It Works:
- • >50% support = Auto-pass (51% = 99% = pass)
- • <50% support = Auto-fail (49% = 1% = fail)
- • Changing laws via Parliament costs 50% support points
Best First Debate:
"Expand Gravel Road Network" - Gives +10 centralization push and makes roads cheaper to build
Increasing Support:
- • Build monastery: +12% support
- • Reduce opinion of certain nations (varies)
- • Random events during debate period
You can also request CBs through Parliament for dubious claims on neighbors
Priority Law Changes
Use Parliament to change these laws efficiently
By Blood (Feudal Jury Laws)
Faster province integration (critical for conquered territories)
Burger Control Mining
Increases plutocracy and capital economy values
Local Court (Inquisition Laws)
Faster population conversion speed at cost of heretic/heathen opinion (acceptable trade-off)
Strategic Law Change Technique:
- Wait for Parliament to assemble
- Choose a debate that gives high initial support (like forest exploitation)
- Spend 50% support to change law instead of passing debate
- You lose the debate bonus but change law for fraction of stability cost
Estate Privilege Management
Balance power, loyalty, and bonuses
Revoking Privileges - Cost Formula:
Stability Cost = Base Cost × Estate Power × Crown Power × Communalism
Example: Communal Lands
- • Base cost: 400 stability
- • Estate power: 9.42
- • Result: 33 stability cost to revoke
Must Revoke First:
Communal Lands (Peasantry)
- • Pushes -0.20 decentralization (kills your crown power)
- • Costs 33 stability to revoke but worth it immediately
- • Revoke in first month despite stability hit
Good Privileges to Grant (Burgers):
Urban Development Grants
+0.01 development/month (compounds with other modifiers to 0.02+)
Commercial Advisory Board
+10% trade capacity (more trade routes = more income)
Building Cost Reduction
Permanent reduction for rest of campaign
Privilege to Eventually Revoke:
Asentistas (Market Fairs)
- • Increases decentralization progress by 0.10
- • Revoke once you can afford the stability cost
- • Not as urgent as Communal Lands
Managing Estate Loyalty:
Population & Culture Management
Population Promotion
How pops grow and fill buildings automatically
How Promotion Works:
- • Pops automatically promote into unfilled building slots
- • Promotion speed = stability × base promotion rate
- • 100 stability = 2× promotion speed
- • High satisfaction also increases promotion speed
Promotion Priority:
Pops promote to fill: Nobility buildings → Clergy buildings → Burgher buildings → Peasant buildings
Capital provinces promote faster. Control and stability are the key multipliers.
Conversion vs Culture Strategy
Two paths to integrate provinces—religion is faster
Religious Conversion (Recommended):
- ✓ Province becomes core at ≥50% Catholic
- ✓ No culture acceptance needed
- ✓ Faster than cultural assimilation
- ✓ Unlock "Local Court" law for +conversion speed
Example: Granada starts 85% Sunni. Convert to 50%+ Catholic → instant core. Skip expensive Andalusian culture acceptance.
Cultural Assimilation (Slow Path):
- • Province becomes core at ≥50% Castilian culture
- • Very slow process (decades per province)
- • Alternative: Accept foreign culture via cultural capacity
- • Cabinet members can be assigned to boost assimilation
Only use this for valuable same-culture-group provinces (Leonese, Galician) or when creating custom vassals.
Culture Acceptance & Discrimination Tiers
Understanding cultural capacity costs and discrimination mechanics
Accepted Cultures
Full bonuses and levy access
- ✓ 100% normal output
- ✓ Can raise levies from these pops
- ✓ No control penalties
- ✓ Normal pop satisfaction
Castile's Starting Accepted:
- • Castilian (primary culture)
- • Catalan (accepted)
Tolerated Cultures
Moderate penalties
- • Reduced output
- • CANNOT raise levies
- • Minor control debuff
- • Lower pop satisfaction
Same culture group cultures default to Tolerated if not accepted. Consider accepting if you need military manpower.
Discriminated Cultures
Severe penalties
- ✗ Massively reduced output
- ✗ CANNOT raise levies
- ✗ Major control penalties (-10% satisfaction)
- ✗ High unrest and rebellion risk
Examples for Castile:
- • Andalusian (from Granada)
- • Moroccan, Berber (from Africa)
- • Aragonese (if conquered, not PU)
Cultural Capacity Costs:
Same Culture Group (Cheap):
- • 0.15 cultural capacity
- • Examples: Leonese, Galician, Aragonese
- • Accept these immediately if you control their lands
Different Culture Group (Expensive):
- • 2.8 to 5.7+ cultural capacity
- • Examples: Andalusian, Portuguese, Moroccan
- • Castile starts with only 2.0 cultural capacity total!
The Vassal Culture Trick:
When you create a custom vassal with a foreign culture as their primary (e.g., Andalusian vassal from Granada lands), you can then improve cultural opinion with that vassal nation.
How it Works:
- Create custom vassal (e.g., "Andalusia") with Andalusian as primary culture
- Go to Diplomacy → Improve Cultural Opinion with Andalusia
- Cultural acceptance cost drops from 5.7 → 2.8 capacity
- 50-year cooldown on this action
- By the time you annex the vassal, culture is cheap to accept or already converted
Religion & Papal Mechanics
Excommunication Votes
How to avoid becoming an international target
How Excommunication Works:
- • Catholic nations can propose excommunication bulls via the Curia
- • All Catholic nations vote based on their grade power score
- • France typically has 6+ votes due to large size
- • If passed, all Catholics can attack you penalty-free
Prevention Strategy for Castile:
- Maintain good relations with France (they control most votes)
- Keep opinion above +100 through gifts, royal marriages, alliances
- Never antagonize the Pope or large Catholic nations
- Support France's excommunication proposals to curry favor
- If threatened, bribe cardinals or improve Papal influence
Castile Example (1350s):
Despite aggressive Aragon conquest, maintained +150 opinion with France through alliance and royal marriage. France voted against excommunication bulls targeting Castile, preventing international war.
Calling Crusades
Holy wars and their massive logistical challenges
How Crusades Work:
- • Initiated via Curia interface when Papal influence is high
- • Targets non-Catholic nations (Muslims, Heathens)
- • All Catholic nations can join for prestige and rewards
- • Common targets: Mamluks, Ottomans, Granada
Castile's Crusade Strategy:
Early Game (1337-1370):
Don't participate actively. Levies cannot reach Egypt or Anatolia without dying. Let allies do the heavy lifting. You can support crusades against Granada since it's right on your border.
Mid-Late Game (1370+):
Once you have professional armies and maritime presence in the Mediterranean, you can send troops via naval transport. Establish supply agreements with allies controlling land routes.
Alternative: Support Without Fighting
- • Send monetary contributions via Curia interface
- • Gain Papal influence and prestige without military commitment
- • Let France, Austria, Hungary field the armies
- • Focus your military on profitable Iberian/North African wars
The Western Schism Event
Choosing between Rome and Avignon - major diplomatic consequences
What is the Western Schism?
A major event in the 1370s-1400s where the Catholic Church splits into two competing Papacies: Rome (Italian faction) and Avignon (French faction). Every Catholic nation must choose a side.
Support Rome
Who Supports Rome:
- • Italian states (Venice, Milan, Papal States)
- • Some German princes
- • England (usually, to spite France)
Consequences:
- • Relations penalty with Avignon supporters (France!)
- • Bonus with Rome supporters
- • Access to Rome Curia interface
Support Avignon (France)
Who Supports Avignon:
- • France (dominant power)
- • Scotland
- • Some Spanish kingdoms
Consequences:
- ✓ Maintain good relations with France
- ✓ France protects you from excommunication
- ✓ Access to Avignon Curia interface
- ✗ Relations penalty with Rome supporters
Why Castile Should Support France:
France is your northern neighbor and controls 6+ excommunication votes. Supporting their Papal candidate:
- • Prevents France from declaring war on you
- • Secures French votes against excommunication bulls
- • Allows alliances and royal marriages to continue
- • France is stronger than Italian states combined
Inquisition Laws & Religious Conversion
Speed up conversion at the cost of religious tolerance
Inquisition Legal Framework:
EU5 includes a set of Inquisition laws under the legal codes system that dramatically affect religious conversion speed and tolerance. These are critical for Castile given the need to convert Granada, Morocco, and other Muslim territories.
Key Inquisition Laws:
Local Court (Priority #1)
Benefits:
- • +Local conversion speed
- • Significantly faster religious conversion
- • Stacks with cabinet member assignment
Drawbacks:
- • Heretics and heathens have reduced opinion
- • Minor unrest in non-Catholic provinces
Show Unity of Faith
A province-specific action (not a law) available via province interface when religious unrest is high.
Effects:
- • +50% local conversion speed
- • Unrest reduction in that province
- • Duration: 10-20 years
- • Can be used repeatedly
Castile's Conversion Strategy:
Step-by-Step Approach:
- Early 1340s: Conquer Granada (85% Sunni Muslim)
- Mid 1340s: Assign high-skill cabinet member to religious conversion in Granada provinces
- 1350s-1360s: Pass "Local Court" law via Parliament for +conversion speed
- 1360s-1370s: Use "Show Unity of Faith" action on stubborn provinces
- Result: Granada fully Catholic by 1380s, provinces become cores automatically at ≥50% Catholic
Timeline Example from Transcript:
Granada conquered 1340 (85% Sunni) → Local Court passed 1358 → Assigned Fadrique de Castro (98 military) to conversion → Provinces hit 50% Catholic by 1365-1375 → Auto-cored without cultural acceptance → Fully integrated by 1380s despite Andalusian culture remaining discriminated.
Trade-offs: Tolerance vs Conversion Speed
High Tolerance (Avoid Inquisition Laws):
- ✓ Better relations with non-Catholic nations
- ✓ Lower unrest in conquered territories
- ✓ Diplomatic flexibility
- ✗ Very slow conversion (decades per province)
- ✗ Provinces remain discriminated culture with low control
- ✗ Cannot core provinces quickly
Fast Conversion (Inquisition Laws) - Recommended:
- ✓ Provinces core in 10-20 years instead of 50+
- ✓ Unlock full tax/manpower potential quickly
- ✓ Skip cultural acceptance system entirely
- ✓ Granada, Morocco fully integrated before colonization
- ✗ Minor opinion penalty with Muslim nations (who you're at war with anyway)
- ✗ Temporary unrest (manageable with garrison)
War & Diplomacy Strategy
The Iberian Wedding Controversy
Two paths to unify Iberia - choose wisely
Option A: Aggressive Conquest
Rationale:
"Every trial run, the French wipe out Aragon before the Iberian Wedding triggers"
Strategy:
Attack Aragon early (1337-1340s) before France devours them. Use "Claims on Province" CB on Cuenca (your core that Aragon holds).
Pros:
- ✓ Control your own destiny
- ✓ Grab land immediately
- ✓ Form vassals for auto-integration
- ✓ No RNG dependency
Cons:
- ✗ Aggressive expansion penalties
- ✗ Takes 2-3 wars to complete
- ✗ Costs manpower and ducats
Execution:
- Build spy network to 20 in Aragon
- Create claim on provinces (Cuenca)
- War 1: Grab northern chunk, keep Cuenca to reuse CB
- War 2: Take central territories
- War 3: Final annexation including Cuenca
- Create vassals (Valencia, Barcelona, Zaragoza)
Option B: Iberian Wedding
Rationale:
Historical event that grants Aragon in personal union peacefully
Requirements:
- Royal marriage with Aragon
- RNG event trigger (timing uncertain)
- Aragon must still exist
Pros:
- ✓ No aggressive expansion
- ✓ Peaceful unification
- ✓ Potential Naples inheritance
- ✓ Historical authenticity
Cons:
- ✗ RNG timing (can take decades)
- ✗ France may conquer Aragon first
- ✗ Very long integration time
- ✗ Risky dependency on luck
If Choosing This:
- Ally Aragon immediately
- Protect them from France
- Maintain royal marriage
- Be prepared to wait (or be disappointed)
Early War Targets (1337-1350)
Systematic Iberian conquest order
Priority #1: Granada
- • Build spy network to 20 for Religious War CB
- • Alternative: Request CB via Parliament for dubious claim
- • Take all provinces, force religion on slaves
- • Create small vassal in conquered territory (auto-integration)
Priority #2: Morocco (via Event War)
- • Join Tlemcen-Morocco war for Strait of Gibraltar
- • Grab 4 North African coastal locations (Ceuta area)
- • Control both sides of strait for maritime presence
- • Create vassal "Masamuda" for auto-integration
Priority #3: Navarre
- • Diplomatic vassalization ideal (improve relations to +20 reasons)
- • If war needed: Attack before France vassalizes them
- • Take Iberian provinces, release Béarn in southern France
- • Create vassal from conquered Navarrese land
Controversial: Portugal (Pre-Union)
- • Grab southern provinces (Alentejo area)
- • Create vassal from conquered land
- • Co-belligerent when attacking Navarre to reduce stability hit
The Vassal Swarm Meta
Vassal Benefits
- Auto-Integration: Vassals integrate conquered provinces themselves (saves cabinet member time)
- Pre-Cored Land: When you annex them, land is already integrated/cored
- Levy Access: Raise levies from accepted pops (you can't levy unaccepted cultures initially)
- Income Tribute: 20% of their income flows to you
- Institution Sharing: 20% of embraced institutions transfer to you
Custom Vassal Creation
Navigate to: Geopolitics → Create Subject → Custom Subject
Three Subject Types:
Cannot annex, minimal income, fast primary pop growth (use in New World)
Can annex after 10 years, 20% income tribute, 20% institution embrace
Direct king control (less useful for Castile)
Cultural Opinion Trick
Advanced strategy to reduce culture acceptance costs
- 1Create vassal with "problem" culture as primary (e.g., Andalusian from Granada)
- 2Improve cultural opinion with that vassal (10-year cooldown)
- 3Acceptance cost drops from 5.7 to 2.8 cultural capacity
- 4By the time you annex vassal, culture is accepted cheaply or fully converted
This technique is especially useful for Andalusian, Aragonese, and Basque cultures in Iberia.
Recommended Iberian Vassals
Create 3-5 small vassals across conquered lands
Andalusia (Granada lands)
Converts to Catholic over time, use cultural opinion trick
Alentejo (Southern Portugal)
Already Catholic, Portuguese culture
Valencia (Eastern Aragon)
Aragonese Catholic, quick integration
Barcelona (Northern Aragon)
Aragonese Catholic, coastal trade benefits
Navarre (Basque lands)
Converts over time, strategic mountain passes
Military Composition & Combat
Levies vs Professional Army
Levies (Starting Forces)
- • Start with 49,000 men
- • Free to raise but have major limitations
- • Cannot refill garrisons
- • Die rapidly to attrition without supply
- • Shrink after each use (~25K after first war)
- • Decrease with population loss
Professional Army (1370s+)
Unlock via Renaissance advance "Organized Military"
- • Can refill garrisons
- • Better supply management with camp followers
- • Maintain standing army for rapid response
- • Higher quality troops
Naval Strategy
Maritime Presence
Ships stationed in sea tiles increase maritime presence, reducing proximity cost through sea tiles. Critical for controlling islands and coastal provinces.
20 ships per fleet, assign to patrol 4 sea tiles each
Brethren of the Marsh
Unique Castilian building in marshes that provides 10 sailors/month and enables shipbuilding. Build these early!
Combat Lessons - Learn from Mistakes
Real examples from campaign gameplay
Combat Pro Tips:
- • Province capitals: Sieging the capital captures the entire province. Non-capital sieges only take that location.
- • Supply management: Get food access agreements or stay on coastlines where your fleet can supply armies
- • Camp followers: Essential for inland campaigns—levies have minimal food storage
- • Positioning matters: Regiment positioning in battles significantly affects casualties
Surviving the Black Death
The Plague (1340s-1350s)
Usually hits Sevilla first, spreads rapidly
Best Event Choice:
"Segregate the Infected"
Costs: 10 stability
Gains:
- +15 disease resistance during outbreak
- Communalism push (helps revoke privileges)
Long-term Benefits:
- • Affected provinces gain 84%+ disease resistance
- • Future outbreaks kill significantly fewer
- • Pop promotion speeds up (less competition for jobs)
- • Buildings have worker shortages initially but recover
Economic Response Strategy:
- • Don't panic-build—wait for population recovery
- • Focus on infrastructure that doesn't need pops (roads, marketplaces)
- • Maintain high stability to promote faster population promotion
- • Accept temporary 600+ burger shortages in major cities
- • Your tax base will recover within 10-20 years as pops refill positions
Historical note: Delhi lost 8 million in the same outbreak. Castile's 2.2 million death toll, while devastating, is relatively moderate.
Colonization: When & How
Why Wait Until 1420s?
The cost of exploration (10-15 ducats/month) seems small, but it's massive compared to your early income. That money compounds much faster when invested in your economy.
Early Game (1337-1420):
- • Build marketplaces (100% profit)
- • Construct road network (control boost)
- • Expand RGOs (tax base growth)
- • Max out trade routes
Goal: Tax base from 169 to 500+ ducats/month
By 1420s:
10 ducats becomes trivial income. You can explore 9 sea tiles simultaneously, send multiple colonists, and completely overshadow other colonizers.
How to Colonize
Step 1: Exploration
Navigate to: Geopolitics → Territory
- Assign courtiers to explore sea tiles (~10 ducats/month)
- Start with closest: Azores Sea, Madeira Sea
- Exploration progress shown (0.0 out of 4.92, etc.)
- Estimated completion time varies by tile
Step 2: Land Exploration
Assign courtiers to explore discovered lands (Azores, Canary Islands)
Step 3: Sea Charters
Navigate to: Colonies → Sea Charters
- Choose source province (send Castilians from Madrid/Toledo)
- Colonists migrate automatically
- Creates territories over time
- Azores and Canary Islands = stepping stones to New World
Campaign Timeline
1337-1340: Foundation
- • Setup: Cabinet, forts, privileges, crown power
- • Join Morocco-Tlemcen war, grab Gibraltar strait
- • Attack Granada with Religious CB
- • Build marketplaces and roads aggressively
1340-1350: The Black Death
- • Plague arrives—choose "Segregate the Infected"
- • Continue Iberian conquest (Navarre)
- • Attack Portugal to shrink pre-union
- • First Aragon war (if aggressive strategy)
- • Create vassal swarm across conquered lands
1350-1370: Unification
- • Second/third Aragon wars (complete conquest)
- • Parliament law changes (By Blood, Burger Control)
- • Portugal personal union event triggers
- • Unlock Renaissance advances (Professional Army)
1370-1390: Consolidation
- • Establish PU seniority over Portugal
- • Begin centralizing Portugal union (5 laws over 50 years)
- • Form Spain (sufficient land + integrated vassals)
- • Transition to professional standing army
- • Unlock Inquisition laws
1390-1420: Economic Boom
- • Continue integrating Iberian vassals
- • Push into North Africa (Morocco expansion)
- • Build up economy (RGOs, development, trade)
- • Prepare for colonization age
1420+: Colonial Empire
- • Begin systematic exploration (Azores, Canaries, New World)
- • Launch sea charters, establish colonial nations
- • Integrate Portugal union (after 50-year centralization complete)
- • Expand colonial empire globally
Advanced Tips & Meta Knowledge
Courtier Hiring Cost Explosion
From 540 ducats to 30,000+ ducats - plan ahead or pay the price
The Exponential Cost Curve:
1337-1350s
540
ducats/courtier
1400-1450
3,000
ducats/courtier
1500-1550
12,000
ducats/courtier
1600+
30,000+
ducats/courtier
Courtier Depletion Causes:
Natural Attrition:
- • Courtiers die of old age (50-70 years typical)
- • Generals die in battle
- • Governors/cabinet members die while serving
- • No automatic replacement mechanism
Diplomatic Loss (Critical Bug/Feature):
- • Your heirs can become courtiers in their mother's nation
- • Example: Castile heir married to Navarre princess → heir becomes Navarre courtier
- • You lose the courtier permanently
- • This happened in the transcript, depleting Castile's pool
Courtier Preservation Strategies:
- Arrange marriages between your own courtiers - generates new courtiers without hiring
- Marry foreign princesses strategically - be aware heirs may defect to mother's nation
- Hire courtiers in early game (540 ducats) - invest 2,000-3,000 ducats in 1340s-1360s for 4-5 courtiers
- Don't waste courtiers on low-skill tasks - check military/administrative skills before assigning
- Keep 8-12 courtiers minimum - you need 2 cabinet + generals + governors + reserves
- Priests cannot marry - avoid making too many courtiers into clergy
Real Campaign Example (from transcript):
By the 1370s, the player noticed their courtier pool had shrunk from 8 to 4 due to:
- • 2 courtiers died in battles commanding armies
- • 1 heir became a Navarre courtier after royal marriage
- • 1 cabinet member died of old age
Solution: Hired 3 new courtiers for 540 ducats each (1,620 total) in 1375. By 1450, the same action would cost 9,000 ducats.
Cabinet Management Best Practices
Maximize efficiency and minimize stability costs
Cabinet Member Assignment Strategy:
The 5 Stability Cost Problem:
Every cabinet member change costs 5 stability. With only 2 cabinet slots initially, frequent changes drain your stability budget.
Optimal Assignment Approach:
Early Game (1337-1350):
- • Slot 1: Stability Investment (permanent until 100 stability)
- • Slot 2: Monthly Legitimacy (permanent until 100 legitimacy)
- • Don't change until both reach 100
Mid Game (1350-1380):
- • Slot 1: Province Integration (high military skill courtier)
- • Slot 2: Religious Conversion OR Centralization Push
- • Change only when task complete (months to years per assignment)
Late Game (1380+):
- • Slot 1: Technology Research (high administrative skill)
- • Slot 2: Trade Network Optimization OR Estate Management
Skill Ratings Matter Enormously:
Military Skill (Integration/Conversion):
- • 98 military: 18 months per province
- • 60 military: 30 months per province
- • 40 military: 45+ months per province
- • Difference: 2-3× speed variation
Administrative Skill (Research/Economy):
- • High admin: Faster technology unlock
- • Affects development speed
- • Impacts trade efficiency calculations
- • Less dramatic than military difference
Cabinet Expansion Timeline:
Castile starts with only 2 cabinet slots. You can expand to 3-4 slots through government reforms and laws.
- • 1337-1360: 2 cabinet slots (focus stability + legitimacy)
- • 1360-1390: Unlock 3rd slot via government reform (integration + conversion + values)
- • 1390+: Potentially 4th slot via advanced reforms (depends on centralization)
More cabinet slots = less need to change assignments = stability savings = faster growth
Rebellion Handling Strategies
When to bribe, when to crush, and how to prevent
Three Approaches to Rebellions:
Prevention (Best)
- ✓ Keep estate loyalty above 50%
- ✓ Grant privileges strategically
- ✓ High control reduces rebellion risk
- ✓ Population satisfaction above 80%
- ✓ No cost, no disruption
Bribe (Short-term)
- • Costs 200-1,000 ducats
- • Temporary satisfaction boost
- • Estate becomes wealthier
- • Rebellion delayed, not solved
- • Use when you can't afford war
Crush (Long-term)
- ✓ Permanent solution
- ✓ Estate loses wealth/power
- ✗ Costs manpower
- ✗ Provinces lose control (reset to ~0%)
- ✗ Years to recover
Rebellion Mechanics Deep Dive:
What Triggers Rebellions:
- • Estate satisfaction drops below 50% (rebellious status)
- • Low population satisfaction (below 60%)
- • High separatism in recently conquered provinces
- • Religious/cultural discrimination in provinces
- • Economic downturn reducing estate income
Rebellion Consequences:
- • Control reset to 0-10% in affected provinces (catastrophic)
- • Army raised by estate (typically 10-30K troops)
- • If rebellion wins: estate forces privilege grants or worse
- • If you crush: takes 2-5 years to rebuild control in provinces
- • Trade income, manpower, tax all drop during recovery
Castile-Specific Rebellion Strategy:
Early Game (1337-1360): Prevention Only
You cannot afford rebellions when control is already low (16-20%). Focus on:
- • Grant privileges liberally (even bad ones temporarily)
- • Keep estate satisfaction above 60%
- • Bribe if satisfaction drops to 50%
- • Build control through roads and stability first
Mid Game (1360-1400): Selective Crushing
Once control is high (60-80%) and you have professional armies:
- • Revoke bad privileges (Communal Lands, Army Taxation)
- • If estates rebel, crush them decisively
- • High base control means recovery is 6-12 months, not years
- • Weaken estates permanently by defeating rebellions
Late Game (1400+): Total Control
With 80-100% control and strong economy:
- • Systematically revoke all negative privileges
- • Crush any rebellion immediately
- • Recovery is 2-4 months due to infrastructure (roads, stability)
- • Estate power permanently reduced
Achievement Unlocks from Campaign
Milestones and achievements unlocked following this strategy
Following the strategies outlined in this guide, the original playthrough unlocked these achievements and milestones:
Formation of Spain
Unlocked: ~1390-1400 (after integrating Iberian vassals)
Required: Control all of Iberia (Castile, Aragon, Navarre, Portugal in PU or integrated), Catholic religion, centralization above 50
Mare Nostrum
Progress: Partial (controlled Gibraltar strait, North Africa coastline)
Full achievement requires controlling entire Mediterranean coast (takes until 1500s-1600s)
Renaissance Man
Unlocked: 1370s (unlocked all Renaissance advances)
Required: Unlock Organized Military, Banking System, Navigation Improvements, etc.
Colonial Empire
Progress: Begins in 1420s (exploration of Atlantic, Caribbean)
Full achievement requires establishing colonial nations in 3+ colonial regions
The Reconquista
Unlocked: 1345-1350 (conquered Granada completely)
Required: Conquer and convert Granada to Catholic (historical achievement)
Survived the Black Death
Unlocked: 1350s (survived plague with "Segregate Infected" choice)
Granted disease resistance bonuses to affected provinces
Common Exploits & Bugs to Avoid
Broken mechanics that ruin the learning experience
Known Exploits in Early EU5 Versions:
1. Infinite Courtier Marriage Loop
Exploit: Arranging marriages between courtiers, canceling them immediately, and remarrying generates infinite courtiers without costs.
Why Avoid: Breaks courtier scarcity mechanic entirely. Defeats the purpose of courtier management.
2. Estate Rebellion Control Loop
Exploit: Granting and immediately revoking the same privilege repeatedly to manipulate estate loyalty without consequences.
Why Avoid: Removes strategic decision-making around estate management. Makes stability meaningless.
3. Naval Attrition Cheese
Exploit: Loading armies onto transports to avoid land attrition during long sieges, then unloading only for battles.
Why Avoid: Breaks supply line mechanics. Makes distant wars trivial without proper logistics.
4. Save-Scum Royal Marriage RNG
Exploit: Reloading saves repeatedly to manipulate random events like Iberian Wedding, personal union triggers, or heir traits.
Why Avoid: Defeats the purpose of strategic planning. The guide recommends aggressive conquest instead of RNG reliance.
5. Province Development Overflow
Bug: In some early versions, development investment could overflow negative, causing provinces to lose development instead of gain when spamming the button.
Why Avoid: This is an actual bug (not exploit), but be aware when developing provinces manually. Stop if development decreases.
Recommended Approach: Ironman Mode
For the best learning experience and to prevent temptation to exploit/save-scum:
- • Enable Ironman mode when starting campaign
- • Autosaves prevent reloading to manipulate RNG
- • Forces you to adapt to events instead of min-maxing outcomes
- • Makes achievements meaningful
- • Builds better strategic thinking and contingency planning
The strategies in this guide work in Ironman mode without exploits, creating a challenging but fair campaign.
Common Mistakes to Avoid
Waiting for Iberian Wedding
France usually devours Aragon before the event triggers. Take control of your destiny.
Direct Law Changes
Never pay 100 stability when Parliament costs only 50% support. Always use Parliament!
Wrong Fort Locations
Only provincial capitals need forts. Non-capital forts waste money and don't protect the province.
Ignoring Crown Power
At 23% crown power, you lose 77% of your trade income. This is devastating!
Low Control Provinces
20% control means you're losing 80% of tax, manpower, and benefits. Build roads and increase stability!
Early Colonization
Colonizing before 1420s wastes ducats that compound better in your economy.
Assaulting Forts
Massive casualties for minimal gain. Be patient and siege normally.
No Supply Lines
Levies die to attrition inland without food access. Get military access or stay coastal!
Large Vassals
Small vassals integrate faster and are easier to manage. Keep them 2-3 provinces max.
Ignoring Roads
Roads give -20% proximity cost and dramatically boost control. Build them everywhere!
Frequent Cabinet Changes
Each change costs 5 stability. Pick cabinet members with balanced stats across all abilities.
Not Using King as General
Missing +25% crown power bonus is a huge mistake. Always assign king to army command!
Why This Guide is Accurate
This guide is based on actual EU5 gameplay from a complete Ironman achievement campaign, not theory or outdated EU4 mechanics.
Note: Guide written for EU5 version 1.0.8. Mechanics and strategies are current as of this patch.
