Germany: KAISER SIGNS ORDER FOR RETIREMENT TO SIEGFRIED STELLUNG (Operation Alberich ). Whole zone between existing fighting front and pillbox-studded new line (65 miles from near Soissons to Arras, average depth 19 miles) is given rigorous scorched earth treatment. New line will shorten Western Front by 25 miles and release 13 divisions into reserve. British not accurately aware of Hindenburg Line until February 25.
Mesopotamia: Turks evacuate Hai triangle east of Canal for new line in Dahra Bend, including Kut south bank liquorice factory. British losses since December 13: 8,524 soldiers – but higher Turk ones including 2,006 buried and 578 PoWs.
Turkey: Grand Vizier Said Halim resigns, Young Turk Talaat Bey succeeds, made Pasha.
Law fixes universal military service 20-45 years.