Origins of World War I Board Game

Origins of World War I is a free print-and-play game by legendary wargames designer James Dunnigan. The game was re-implemented as Origins of World War II, an Avalon Hill game now long out of print. From the description:

A political/strategy game in which five players represent the five major nations in pre-World War I Europe. They must compete against each other to achieve each nation’s ‘national objectives’. While actual war is not allowed in the game, the play should show quite clearly how tensions developed to such a high pitch in 1914.

France 1914 Board Game

Lou Coatney’s France 1914 is a free print-and-play, hex-and-counter boardgame of the German attack on France in 1914.

The Lights Are Going out WWI Rules

The Lights Are Going Out is a set of free wargames rules for WWI in 1914. The rules are designed for 15mm figures.

1916 World War I Rules

Wartime Journal offers 1916, a set of free wargames rules for battalion and regimental combat in World War I.

First World War History Website

First World War dot Com is a good resource for doing research into the war to end all wars.