The term "Boyars" refers to the noble class in Russia and Eastern Europe during the medieval period. They were powerful landowners who played a significant role in the governance and military affairs of their regions. Boyars often served as advisors to the ruling princes and were influential in shaping the political landscape of their time. Boyars were known for their wealth and status, often living in large estates and enjoying privileges that common people did not have. Their power began to decline with the rise of centralized authority, particularly under leaders like Ivan the Terrible, who sought to reduce their influence and strengthen the monarchy.