20 August

1914

 * - Brussels evacuated by the Belgians and occupied by the Germans. Namur bombarded.
 * Lorraine: Powerful German counter-attack near Saarburg and Morhange drives French back.
 * British concentration Avesnes-Le Cateau completed.
 * - East Prussia: Battle of Gumbinnen. Russian victory followed by occupation of the town, Goldap and Lyck.
 * - Serbia: Disorderly flight of Austrians towards the frontier.
 * No - East Africa: Taveta occupied by the Germans: Uganda Railway attacked.
 * - Rome: Death of Pope Pius X.

1915

 * - Russians evacuate Byelostok; enemy occupies Byelsk (north of Brest).
 * - Topkaneh (Arsenal at Constantinople) bombed by Russian aviators.
 * No - Naval battle of Riga continues. German Fleet penetrates Gulf.
 * - Italy declares war on Turkey.
 * Second reading of War Loan Bill in Reichstag. 1,000,000,000 marks voted.