Line (formation) in the context of "Battle of Breitenfeld (1631)"

Count Pyotr Alexandrovich Rumyantsev-Zadunaisky (Russian: Пётр Алекса́ндрович Румя́нцев-Задуна́йский; 15 January [O.S. 4 January] 1725 – 19 December [O.S. 8 December] 1796) was one of the foremost Russian military commanders of the 18th century, widely considered to be one of Russia's greatest military leaders and is referred to as one of the greatest commanders in military history. As a commander, he is placed on par with Alexander Suvorov. Rumyantsev used mobile divisional squares for the first time in history as opposed to linear battle orders and initiated the formation of light (jaeger) battalions in the Russian Army, which operated in a scattered order.

He governed Little Russia in the name of Empress Catherine the Great from the abolition of the Cossack Hetmanate in 1764 until Catherine's death 32 years later. Monuments to his victories include the Kagul Obelisk in Tsarskoye Selo (1772), the Rumyantsev Obelisk on Vasilievsky Island (1798–1801), and a galaxy of Derzhavin's odes.

In military terminology, a column is a tactical formation of fighters moving together in one or more files in which the file is significantly longer than the width of ranks in the formation. The column formation allows the unit rapid movement and a very effective charge (due to weight of numbers), and it can quickly form square to resist cavalry attacks, but by its nature only a fraction of its muskets are able to open fire.

The line formation offers a substantially larger musket frontage than the column, allowing for greater shooting capability, but requires extensive training to allow the unit to move over ground as one while retaining the line. It is also applied by modern armies to vehicles, troops and naval vessels.

Heavy infantry consisted of heavily armed and armoured infantrymen who were trained to mount frontal assaults and/or anchor the defensive center of a battle line. This differentiated them from light infantry who were relatively mobile and lightly armoured skirmisher troops intended for screening, scouting, and other tactical roles unsuited to soldiers carrying heavier loads. Heavy infantry typically made use of dense battlefield formations, such as shield wall or phalanx, multiplying their effective weight of arms with force concentration.

Heavy infantry were critical to many ancient armies, which first attested by the Sumerians in the Stele of the Vultures. It was also used by rival Assyrian and Persian Sparabara, then by Greek hoplites, Macedonian phalangites, and Roman legionaries. After the fall of Rome, heavy infantry declined in Europe but returned to dominance in the Late Middle Ages with Swiss pikemen and German Landsknechts. With the rise of firearms during early modern warfare, dense formations became increasingly infeasible, and heavy armours were either ineffective or too cumbersome to be tactically useful. By the early 18th century, heavy infantry were replaced by line infantry armed with muskets and bayonets and wearing little to no armour.