Italian Front: BATTLE OF CAPORETTO (TWELFTH ISONZO, until November 9) begins on misty, rainy day with 0200 hours hurricane bombardment of 4 hours (including 2 hours of gas shells that Italian gas masks unable to cope with so guns fall silent). Austro-German assault (10 divisions) at 0800 hours on 20-mile front penetrates along valleys up to 14 miles isolating, panicking and destroying 3 Italian divisions (18,000 PoWs and 100 guns) east of Upper Isonzo, although flanking armies’ attacks fail. German 12th (Silesian) Division takes Caporetto at 1530 hours. Cadorna belatedly calls up 9 reserve divisions and orders Tagliamento defences. Austrian Jewish-born lyric poet Lieutenant Franz Janowitz (2nd Tyrol Sharpshooter Regiment) mortally wounded by MG in assault on Mt Rombon, dies on November 4, aged 25.
Brazil: Troops seizes 43 interned German merchant ships.
North Sea: Harwich Force flagship cruiser Centaur badly damaged by own depth charges washed overboard after vain night sortie to catch German destroyers.
Baltic: Royal Navy submarine C32, trapped in Gulf of Riga, beaches in Vaist Bay west of Pernau. Russian submarine Gepard probably mined on October 28, but trapped British C26 (Downie) reaches Hangoe (Finland) at third attempt on December 13.
Germany: 9 Handley Page bombers (2 lost) of RNAS ‘A’ Squadron and 14 FE2bs (2 lost) raid industrial and rail targets in Saarbruecken area.
Italian Front: Caproni bombers make 18 raids on Austro-German troops (until c. November 14) but forced to move bases behind Piave.