Kaloyan of Bulgaria

Ivan II , known as Kaloyan the Greekslayer or alternatively as the Romanslayer , ruled as emperor of Bulgaria between 1197 and 1207. He is the third and youngest of the brothers who managed to restore the Bulgarian Empire, the others being Peter IV and Ivan Asen I. Kaloyan managed to stabilize the tsars power and the Second Bulgarian Empires position as a leading power in Southeastern Europe thanks to his successful campaigns against the Latin Empire.

Kaloyan was born in about 11681169. He was the younger brother and heir of Peter IV of Bulgaria and Ivan Asen I. He and his brothers have disputed origin. In 1187 he was sent as a hostage to Constantinople, from where he escaped and returned to Bulgaria about 1189. After both of his brothers were assassinated by Ivanko, Kaloyan got an advantage over the conspirators and became the Tsar of Bulgaria.

Source: Wikipedia