20 December

Western Front

 * Battle of Givenchy continued.
 * Furious German attacks on Indian troops.

Eastern Front

 * Poland: Russians holding the Bzura River against heavy German assaults.
 * Galicia: Russians begin to counter-attack and to recover the Carpathian Passes.

Asiatic and Egyptian Theatres

 * Armenia: Russians defeat the Turks near Lake Van.

Naval and Overseas Operations

 * South Africa: Captain Fourie shot; his brother's sentence commuted.