The game was released for Microsoft Windows in January 2007, and was later ported to Mac OS X by Virtual Programming in November 2007.

The original game without expansions starts in 1453, right after the Fall of Constantinople, and continues to 1789, just past the beginning of the French Revolution.

Players can influence a nation's society and values by adjusting "sliders" such as free trade/mercantilism, and may hire court advisors such as Wolfgang Amadeus Mozart.

As the game advances, players can pick "national ideas" such as Liberté, Égalité, Fraternité, which give specialized bonuses.

The game has over 300 playable countries, including giants like Ming China, regional powers like Bohemia and Kazan, and tiny nations like the Maldives.

Early international institutions such as the Holy Roman Empire, the Papal Curia and with the Divine Wind expansion the Shogunate are simulated in some depth.

Aggression (seizing provinces without a rightful claim) is checked by the "badboy" system of international infamy common to Paradox's games.

Often the game diverges from reality after some time in-game, with unhistorical events such as Portugal colonizing North America, or Poland-Lithuania surviving to bully its neighbors.

An expansion pack named Napoleon's Ambition was released on 22 August 2007 via GamersGate, a digital distribution platform.

The Windows version of the expansion is available as a download from GamersGate or as part of the Europa Universalis III Complete retail package, and aims to expand on EUIII with an improved interface, an enhanced trade system, expanded options, and the inclusion of more content to cover the extended time period.

For instance, a player can choose to create the United Kingdom, make Paris "worth a Mass", or institute an East Indian Trade Company.

The players can now choose between crushing rebels using military force, negotiating with them, or leaving them and watching them enforce their demands on your country.

The third expansion titled Heir to the Throne was released for Windows on 15 December 2009 and includes many features requested by members of the forum.

With 46% of the votes, the poll was won in favour of a Europa Universalis III expansion which is to focus on the rest of the world.

He also claimed that Paradox did not own the source code licensed to him, and announced a release of what was to be Magna Mundi the game, now re-titled World Stage.

[22] Nicholas Bale of Game Revolution also gave a positive review, calling it "rich strategic title with a bevy of options available".