Regiment (polk). During the Princely era any separate military unit or expedition that a prince or his vicegerent commanded in time of war was known as a polk (eg, as in the epic Slovo o polku Ihorevi [The Tale of Ihor's Campaign]). In 14th- and 15th-century Lithuanian-ruled Ukraine (see Lithuanian-Ruthenian state) military units raised by the inhabitants of towns and lands to repel Tatar attacks were also known as polky. In the late 16th century under Polish rule, the first regiments of registered Cossacks were formed and named after the towns where their colonel and chancellery were located. Before the 1648–57 Cossack-Polish War six such regiments were based in Bila Tserkva, Cherkasy, Chyhyryn, Kaniv, Korsun, and Pereiaslav. Earlier, from 1630 to 1638, there was also a Myrhorod regiment.
In the Cossack Hetman state the regiment was not only a military but also an administrative-territorial unit (see Company system and Regimental system). It also had mercenary regiments of cavalry and infantry (Serdiuk regiments). An analogous system existed in Russian-controlled Slobidska Ukraine, where in the late 17th century five Cossack regiments defended the southern frontier of the Russian Empire from the Crimean Tatars and Nogay Tatars. In 1764 and the 1770s the Russian regime created lancer regiments in the newly annexed region of New Russia, to which they recruited Cossacks from Poltava regiment and Myrhorod regiment and from Russian and foreign colonists. In the early 1780s the tsarist regime abolished the Cossack regimental system, and in 1784 it replaced it with the Little Russian Cavalry of 10 carabineer regiments as part of the Russian imperial army. Each regiment had 10 squadrons, which were initially organized by territory and commanded by Ukrainian officers. Since that time Russian imperial, Ukrainian (1917–21), and Soviet military formations have been organized along the lines of other European armed forces.
[This article originally appeared in the Encyclopedia of Ukraine, vol. 4 (1993).]