- General Aleksei Brusilov leads a major Russian offensive against Germany and Austria-Hungary on the Eastern Front. 200,000 Germans and Austrians are captured in the first three days of the ‘Brusilov Offensive’ on a 500km wide front stretching from Lutsk to Chernovtsy in present-day western Ukraine. The surprised Germans reassign troops from Verdun as reinforcements. Fighting continues until September; the Austro-Hungarians are forced into a steady retreat, suffering 1.6 million casualties, including 400,000 prisoners of war. The Brusilov Offensive is regarded as the largest and most successful Allied offensive of World War I and among the most lethal offensives in world history in terms of casualties.