Western Front
First units of Portuguese Expeditionary Force land in France (see August 8th, 1916, and June 17th, 1917).
Eastern Front
Galicia: Lechitski attack succeeds near Mt Botosul, 2,218 German PoWs taken between Kimpolung and Jakobeny (January 27 and 30); 3 German night attacks fail on January 31.
Dobruja: Focsani (Rumania) taken by German forces.
Baltic Provinces: Germans take Dvina Island near Glandau northwest of Dvinsk but Russians recover on January 8.
Romania: Cossack Division leaves Rumanian III Corps for Russian one causing gap that Falkenhayn exploits on January 6.
Asiatic and Egyptian Theaters
Arabia: Emir Faisal and his army on the attack. Picture taken by T.E. Lawrence:
http://imgur.com/l0SvLqP* © IWM (Q 58863)
Naval and Overseas Operations:
East Africa: Action of Beho-Beho (until January 4) continues German retreat, but big game hunter Captain Selous DSO, is killed, aged 65 on January 4. Beves’ South African advance guard crosses river Rufiji in four Berthon boats.
Political, etc.
Russia: Imperial family buries Rasputin at Tsarskos Salo by night. His murderers exiled in January 6.
United Kingdom: Admiralty reasserts "immemorial" right of merchant-ships to defend themselves against attack or search by an enemy.