Voyi

Armies of Ukraine
Kyivan Rus' / Kingdom of Galicia–Volhynia Druzhyna (862–1240) Voyi
Polish-Lithuanian Commonwealth Registered Cossacks Zaporozhian Cossacks (1492–1648)
Zaporizhian Host Zaporozhian Cossacks (1648–1775)
Austria-Hungary Legion of Sich Riflemen (1914–1918)
Ukrainian People's Republic Ukrainian People's Army (1917–21) Sich Riflemen (1917–21) Ukrainian Galician Army (1918–19)
Free Territory Revolutionary Insurrectionary Army (1918–1921)
Ukrainian National Government UPRA (1941–1944) Ukrainian Insurgent Army (1941–1955)
Ukrainian SSR Red Cossacks Ukrainian Soviet Army (1918–19) Soviet Armed Forces (1919–1991)
Ukraine Armed Forces (1992–Present)

Armies of Russia
Kievan Rus'
Druzhina 862–1283 Voyi
Grand Duchy of Moscow Tsardom of Russia
Landed army   Streltsy 1400s–1721 New Order regiments
Russian Empire
Imperial Russian Army 1721–1917
White Movement
White Guard 1917–1921
Russian SFSR Soviet Union
Red Army 1918–1946 Soviet Army 1946–1992
Russian Federation
Russian Ground Forces 1992–present

Voyi (singular voi or voy) was a category of armed forces in ancient Rus.

Unlike the standing force druzhina, voi force was drafted from a local population. Next to the druzhina, the voyi formed a basis of an army in Rus'. A Voivode (voi - "army", vode - "to lead", meaning "Warlord") was appointed by a prince (knyaz) in charge of them.