23 December

Western Front

 * Belgians cross the Yser and establish themselves on right bank of Dixmude.

Eastern Front

 * Poland: Germans succeed in crossing the Bzura River at two points.
 * Galicia: Russians compelled to raise the siege of Cracow.

Asiatic and Egyptian Theatres

 * Egypt: Arrival of Australian and New Zealand troops at Cairo.

Political

 * Germany: Captain of the SMS Yorck sentenced to two years' detention for loss of ship.