Rebellion of the brothers Peter and Asen

Uprising of Asen and Peter
Bulgaria during the uprising.
Date 1185–1204 Location Balkan peninsula Result Decisive Bulgarian victory, reestablishment of the Bulgarian Empire
Belligerents
Bulgarian Empire	Byzantine Empire
Commanders and leaders
Ivan Asen I Peter IV Kaloyan	Isaac II Angelos Alexios III Angelos

The Uprising of Asen and Peter (Bulgarian: Въстание на Асен и Петър) was a revolt of Bulgarians and Vlachs living in the theme of Paristrion of the Byzantine Empire, caused by a tax increase. It began on 26 October 1185, the feast day of St. Demetrius of Thessaloniki, and ended with the creation of the Second Bulgarian Empire, ruled by the Asen dynasty.

Isaac II Angelus, in order to raise money for the wedding of the daughter of King Béla III of Hungary, levied a new tax which fell heavily on the population of the Haemus Mountains. They sent two leaders (Peter and Asen) to negotiate with the emperor at Kypsella (now İpsala) in Thrace. They asked to be added to the roll of the Byzantine army and to be granted land near Haemus to provide the monetary income needed to pay the tax. This was refused, and Peter and Asen were treated roughly. Their response was to threaten revolt.

After their return, many of the protesters were unwilling to join the rebellion. The brothers Peter and Asen built the Church of St Demetrius of Thessaloniki in Tarnovo, dedicated to Saint Demetrius, who was traditionally considered a patron of the Byzantine city of Thessaloniki, and claimed that the Saint had ceased to favour the Byzantines: "God had decided to free the Bulgarians and the Vlach people and to lift the yoke that they had borne for so long". This persuaded their followers to attack Byzantine cities, seizing prisoners and cattle. Preslav, capital of the First Bulgarian Empire, was raided, and it was after this symbolic incident that Peter assumed the insignia of Tsar (or Emperor).

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