Avalanche Press' Infantry Attacks series is a World War I version of Avalanche Press' Panzer Grenadier tactical combat series. Infantry Attacks is very similar to Panzer Grenadier -- the two series' use the same map formats and have very similar rules.
Empires End is the first game in the Infantry Attacks series and covers combat on the eastern front during 1914 between Germany, the Austro-Hungarian Empire, and Imperial Russia.