A veteran of World War I, after the February Revolution he joined Bolshevik party and became a chief editor of "Entrenched Truth" newspaper in the 12th Army.
At the end of July 1917 he was arrested by the Russian Provisional Government for defeatism, but was released during the October Revolution.
At the start of the Russian Civil War, Sivers led Red Guards and sailors in the battle at Pulkovo against forces of Krasnov–Kerensky.
Since summer of 1918 Sivers fought at the Russian Southern Front commanded the 1st Special Ukrainian Brigade as part of the 9th Army against the forces of Pyotr Krasnov.
On 15 November 1918 he was mortally wounded in battle near Zhelnovka (today – Zhelunovo, Karachevsky District) and died on 8 December 1918.