The Battle of Orsha was part of a long series of Muscovite–Lithuanian Wars conducted by Muscovite rulers striving to gather all the former Kievan Rus' lands under their rule.

According to Rerum Moscoviticarum Commentarii by Sigismund von Herberstein, the primary source for information on the battle, the much smaller army of Lithuania–Poland (under 30,000 men) defeated a force of 80,000 Muscovite soldiers, capturing their camp and commander.

Albrecht I, Grand Master of the Teutonic Knights, rebelled and refused to give a vassal pledge to Sigismund I the Old of Poland-Lithuania, as required by the Second Peace of Thorn (1466).

Spurred on by this initial success, the Grand Prince of Moscow Vasili III ordered his forces farther into present-day Belarus, occupying the towns of Krichev, Mstislavl, and Dubrovna.

[9] Sigismund left 4,000–5,000 men in the town of Barysau, while the main force, placed under the command of Hetman Konstanty Ostrogski and around 30,000 strong, moved on to face the Muscovites.

[9][11] At the end of August, several skirmishes took place at the crossings of the Berezina, Bobr, and Drut Rivers, but the Muscovite army avoided a major confrontation.

Hetman Konstantyn Ostrogski placed most of his 16,000 horses from the Grand Duchy in the center, while most of the Polish infantry and the auxiliary troops manned the flanks.

[6] The Russian historian A. Lobin tried to calculate the size of the Muscovite army at Orsha based on the mobilisation capacities of the towns which had to send townspeople for military service.

[14] It is known that except for Boyar sons of the sovereign's regiment, the army consisted of people from at least 14 towns: Novgorod, Pskov, Velikie Luki, Kostroma, Murom, Borovsk, Tver, Volok, Roslavl, Vyazma, Pereyaslavl, Kolomna, Yaroslavl, and Starodub.

[15] Based on figures from the well-documented Polotsk campaign of 1563, the author gives the following estimates: 400–500 Tatars, 200 boyar sons of the sovereign's regiment, 3,000 Novgorodian and Pskovians, and about 3,600 representatives of other towns, altogether about 7,200 noblemen.

[6] This calculation method has been backed by Brian Davies (University of Texas at San Antonio),[16] and Russian historians N. Smirnov, A. Pankov, O. Kurbatov,[17] М. Krom,[18] and V.

However, preoccupied with his own wing of the Muscovite forces, he lost track of the other sectors and failed to coordinate a defense against the counterattack by the Lithuanian light and Polish heavy cavalry, which until then had been kept in reserve.

Immediately after the victory, the Polish–Lithuanian state started to exploit the battle for its propaganda aimed at other nations in Europe, with the intent of improving the image of Poland-Lithuania abroad.

"The Polish message was similar to Bomhover's: the Muscovites are not Christians; they are cruel and barbaric; they are Asians and not Europeans; they are in league with Turks and the Tatars to destroy Christendom".

[22] Impressed by the scope of the Lithuanian and Polish victory, Maximilian I, Holy Roman Emperor, started peace negotiations with the Jagiellons in Vienna.

In 1522 a peace was signed, under the terms of which Lithuania was forced to cede to Moscow about a quarter of its possessions within the lands of the former Kievan Rus', including Smolensk.

After the peace agreement of 1522, the Grand Duchy of Lithuania tried to attack Moscow one more time, but major military conflicts were settled for around 40 years.