Boyar, Or Boiar(from ooi, battle), a Slavic title, first especially used by the Bulgarians, Serbs, and Russians, and afterward by the Moldavians and Wallachians. It represented the highest social condition, corresponding in certain respects to that of an English peer. In ancient Russia the boyars were the next after the princes of the blood, and formed a kind of supreme political body, acting as the council of the grand dukes. All the higher offices, civil and military, including the lieutenancies in the provinces, were held by them. While Russia was divided into petty sovereignties, the boyars enjoyed the right of choosing for themselves and for their dependants the prince whom they wished to serve, and of leaving his service at pleasure. When the grand dukes of Vladimir and of Moscow stripped these petty princes of their sovereign rights, the dignity of boyars was granted to them, and their influence often equalled that of the grand dukes, the ukases always containing the words, " approved by the boyars." Precedence among the boyars was according to the creation of the title, which was hereditary; and in the 16th and 17th centuries any boyar of an older creation refused to serve under one of a younger.

This struggle for precedence, which was especially troublesome in times of war, was ended by Fedor III., and Peter the Great wholly abolished the dignity of boyar. In Roumania the boyar nobility, though not of national origin, sat in the council of the hospodars, and exercised a preponderating influence till 1864, when it was checked by Prince Cuza.