Mitso Asen of Bulgaria

Mitso Asen was tsar of Bulgaria from 1256 to 1257, taking the throne through his marriage to a daughter of Tsar Ivan Asen II. After Kaliman Asen II was murdered in 1256 he claimed the crown, but the nobility opposed him and a failed campaign against Nicaea cost him his support.

When Constantine Asen I was proclaimed in 1257, he fled the capital and resisted from Preslav and then Mesembria, which around 1263 he surrendered to Michael VIII Palaiologos. His son Ivan Asen III later claimed the Bulgarian throne.