[1] Zakharov was born on April 23, 1897, in the village of Shilov, Russia (now in the Saratov region), and began military service in 1915.

During the first days of World War II, Zakharov was serving as Chief of Staff of the 22nd Army, which saw action against the German invasion, Operation Barbarossa, in the environs of Vitebsk, Velikie Luki and Nevel.

From August 1941, Zakharov was Chief of Staff and, during October- November, the commander of the Bryansk Front, which covered the Oryol - Tula and L'vov - Kursk axes.

From July 1943, Zakharov commanded the 2nd Guards Army, which performed outstandingly during the penetration of the German defences on the Mius and Molochnaya rivers.

Under his leadership, the 2nd Guards Army broke through powerful fortified positions on the Perekop Isthmus during April 1944 and participated in the liberation of Sevastopol.