Served in Manchuria during Russo-Japanese War, Chief of staff of the Kiev Military District and commander of the XIII Corps, 1912. Chief of staff of the Russian Southwest Army Group (Third, fourth, fifth, and Eighth Armies), and planned the Russian offensive into Galicia. Appointed chief of staff to the Russian Army when the Tsar became Commander-In-Chief, 1915. Disillusioned by the Tsar's increasing isolation, he planned to issue an ultimatum to him for reforms, but was discovered, fell ill and retired in November, 1916. Nevertheless, Alekseev was chosen to procure the Tsar's resignation in March, 1917, and subsequently became Commander-In-Chief under the Provisional Government, but resigned again on 21 May. Following the November Revolution, General Alekseev raised a 'volunteer' army in southern Russia, and became head of the White government after Kornilov's death in March, 1918.