The 51st Lithuanian Infantry Regiment (Lithuanian: 51-asis Lietuvos pėstininkų pulkas;[2] Russian: Литовский 51-й пехотный полк), known as the 51st Lithuanian Infantry Regiment of His Imperial Highness Heir to the Tsarevich (Russian: 51-й пехотный Литовский Его Императорского Высочества Наследника Цесаревича полк, romanized: 51-y pekhotnyy Litovskiy Yego Imperatorskogo Vysochestva Naslednika Tsesarevicha polk) from 1904, was an infantry regiment that served in the Imperial Russian Army.

Having crossed the Vistula in 1813, the Lithuanian regiment was part of the corps besieging Danzig, and then were moved to Poznań.

In the detachment of General Ferdinand von Wintzingerode, the regiment fought in the battle of Leipzig and on 6 January 1814 crossed the Rhine near Düsseldorf.

At the beginning of November Uprising in 1830, the regiment became part of the active army and participated in the battles at Dobre [pl], Wawer and Olszynka Grochowska.

On 19 March 1831, the 1st and 2nd battalions, being in the vanguard of Adjutant General Friedrich Caspar von Geismar, were attacked by the entire Polish army and were completely defeated in the Second Battle of Wawer.

On 3 May 1831, the regiment's remnants arrived in Brest Litovsk, and the Lithuanians began to gradually replenish with the ranks of the 1st and 2nd corps.

In the same year, the 1st battalion took part in several expeditions in Little Chechnya to punish the rebellious Karabuzakhs and skirmished many times with the mountaineers.

In 1845, the 1st battalion was assigned to the Chechen detachment and, participating in the Dargin campaign, distinguished itself in the Ichkerin battle, when capturing the ruins near Gerzel-aul.

Appointed to reinforce the Caucasian troops, the regiment sailed on September 17, 1853 to the shores of the Black Sea coast and, having landed in Sukhumi and Anaklia, headed for the Transcaucasia.

For the next three years, the regiment took part in operations against the mountaineers of the Western Caucasus and was on several expeditions beyond the Kuban and in the Labinsky District.

[7] In Stavropol, the brothers Rtishchevs, who belonged to the regiment, raised the first of the well-known "officer uprisings" against the Communist government.