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Kingdom rankSiam
Primary culture
Central Thai (Thai)

Capital province
Ayutthaya (600)

Mandala System Government monarchy.png

State religion

Technology group
ChineseChinese technology group
Siamese ideas
Ambox outdated info.png Please help with verifying or updating this infobox. It was last verified for version 1.33.

Traditions.png Traditions:

+10% Morale of armies
+30% National manpower modifier

Yearly prestige.png Royal Poets

+0.5 Yearly prestige
−10% Idea cost

Cavalry combat ability.png Advanced Elephant Warfare

+15% Cavalry combat ability
+1 Cavalry fire

Diplomatic reputation.png Experienced Ambassadors

+2 Diplomatic reputation

Development cost.png Encourage Immigration

−10% Development cost

Diplomatic annexation cost.png Consolidation of the State

−20% Diplomatic annexation cost

Technology cost.png Education Reforms

−10% Technology cost

Yearly legitimacy.png Royal Absolutism

+1 Yearly legitimacy
+1.0 Yearly absolutism

Idea bonus.png Ambition:

+5% Discipline

Siam is a formable nation that can be formed by any nation is in the Siamese culture group. Flag of Ayutthaya Ayutthaya can form Siam with the mission Royal Absolutism if the Leviathan.png Leviathan DLC is enabled, however, this takes exceptionally long - deep into the 1600s - as it requires development of 500 and absolutism of 75. A materially faster alternative is to form Siam starting as Lan Xang, a process which could take as little as 10 years, as it requires only five additional provinces three of which are required cores.

Having an Eastern religion means Siam may have tributaries from which it can earn monarch power, ducats or manpower. One of the biggest benefits of such tributaries is that they take no aggressive expansion and act as safe harbours for one's fleet during wars (assuming they are not in the same war).

Formation[edit | edit source]


Execute decision.pngForm Siamese Nation

The Thai peoples must be united under a single state, forging an empire that will dominate South-East Asia.

Potential requirements

The country:

If the country is AI-controlled then it:

Playing with normal or historical nations.


Flag of Siam Siam does not exist.
The country:


The country:

  • AI will always take this decision.
  • AI gives "high priority" (400) to this decision

Events[edit | edit source]

Siamese Revolution icon
Tensions between Europeans and local customs threatened to engulf our nation, now it is all gone.

Missions[edit | edit source]

Main article: Siamese missions

Strategy[edit | edit source]

Have a good strategy for Siam?
+ Add it to this article and help other players!
Please note the style guidelines.

As Ayuthaya better do mission tree: Puppeting Khmer, Mallaca, Lan Ma. That will boost economy, mostly trade. Stay being a Tributary of Ming: There will be a lot of AE and all neighbors are also Tributary of Ming. When Lan Xang dissolves, if gone far in the mission tree, will get Subjigation CB on all Lao countries. If not, just attack them by claims. Now need to swipe culture to form Lan Xang, who can create Siam. If there's posibiity, earn all bonuses, that gives this tag. After all, you form Siam. Be cautious: This makes you no longer a Tributary of Ming.

Country guides

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