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Open Historia

AI Grand Strategy Game

Command nations across all of human history with an AI Game Master. Issue natural language commands. Forge alliances. Wage wars. Rewrite history.

Start a game Open source

Free · open source · bring your own AI key or use the free tier.

·  THE PITCH  ·

The world’s most opinionated Game Master.

Every Paradox game ships with hard-coded events and scripted ledgers. Open Historia ships with an LLM. You type “invade Bohemia” or “send envoy to Ottoman court” and the AI returns the consequences — armies move, treaties shift, relations decay or warm. The Game Master keeps a running summary of your campaign so the world remembers, turn after turn.

Same map. Same start year. Wildly different histories.
·  FEATURES  ·

Three primitives. Endless campaigns.

I

Multi-provider AI

Anthropic, OpenAI, Gemini, DeepSeek, or local. Bring your own key, pick your model per session.

II

Save & share

Turso-backed cloud saves. Resume anywhere, share a campaign URL, fork a friend’s timeline.

III

Alternate history

Rewind to any turn. Branch off. The Game Master rolls the world forward from your new decision.

·  LAUNCH  ·

Pick a scenario.
Rewrite the rest.

20+ presets — historical, modern, alternate, fictional. Or write your own start year, your own nation, your own brief to the Game Master.

Start a game
Free · open source · GitHub