Also found in: Wikipedia.
a unit of Ukrainian cossacks who were accepted for military service by the Polish government in the 16th century and the first half of the 17th and who were included on a special list known as the Register.
A registered-cossack host was created in 1572 by a general edict of the Polish king Sigismund II Augustus for the protection of the southern and eastern borders of the Polish territory and for the struggle against the Ukrainian movement for national liberation. The host at first numbered 300 men headed by the senior officer of the Register, who was designated by the king. The only cossacks recognized by the government were the registered cossacks, officially named the Nizov’e, or Zaporozh’e, Host. They received pay and uniforms and had the right to govern themselves and have their own court. In 1578 the number of registered cossacks was increased to 600, and they were granted the city of Terekhtemirov with the Zarub Monastery (near the present-day city of Pereiaslav-Khmel’nitskii, but on the right bank of the Dnieper), where an arsenal and a hospital were located.
The registered cossacks were a socially heterogeneous group. Although their host starshina consisted for the most part of Ukrainian nobles (szlachta), the rank-and-file cossacks were closely connected with the popular masses and during insurrections repeatedly took the side of the insurgents.
Since the Register conferred various privileges, the Ukrainian peasantry aspired to be included in it. The Polish government was under popular pressure to expand the Register. In the 1630’s it fluctuated between 6,000 and 8,000 men. The Treaty of Zborov of 1649, concluded during the War of Liberation of 1648–54, established the Register at 40,000. After the defeat of the cossacks near Belaia Tserkov’ in 1651, it was reduced to 20,000. After the reunification of the Ukraine with Russia in 1654, the Register was formally set at 60,000 but in fact was no longer compiled.