The Imperial Russian Army was the land armed force of the Russian Empire, active from around 1721 to the Russian Revolution of 1917. In the early 1850s, the Russian army consisted of more than 900,000 regular soldiers and nearly 250,000 irregulars

The Imperial Russian Army entered the Napoleonic Wars organized administratively and in the field on the same principles as it had been in the 18th century of units being assigned to campaign headquarters, and the "army" being known either for its senior commander, or the area of its operations. Administratively, the regiments were assigned to Military Inspections, the predecessors of military districts, and included the conscript training depots, garrisons and fortress troops and MUNITIONS magazines.

In 1806 most of the Inspections were abolished, and replaced by divisions based on the French model although still territorially based. By 1809 there were 25 infantry divisions as permanent field FORMATIONS, each organised around three infantry brigade and one ARTILLERY brigade. When Barclay de Tolly became the Minister of War in 1810, he instituted further reorganization and other changes in the army, down to company level, that saw the creation of separate grenadier divisions, and dedication of one brigade in each division to the jaeger light infantry for skirmishing in open order formations.

Amid the Russian Revolution of 1917 the Imperial Russian Army collapsed and dissolved. The rebellious remnants of the Imperial army evolved to became part of the new RED Army.

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