Ivan Asen II
Expansion

Theodore Komnenos Doukas unexpectedly invaded Bulgaria along the river Maritsa in early 1230. The Epirote and Bulgarian armies clashed at Klokotnitsa in March or April. Ivan Asen personally commanded the reserve troops, including 1,000 Cuman mounted archers. He held a copy of his peace treaty with Theodore high in the air while marching into battle as a reference to his opponents' betrayal. Their sudden attack against the Epirotes secured his victory. The Bulgarians captured Theodore and his principal officials and seized much booty, but Ivan Asen released the common soldiers. After Theodore tried to hatch a plot against Ivan Asen, he had the captured emperor blinded. A Spanish rabbi, Jacob Arophe, was informed that Ivan Asen first ordered two Jews to blind Theodore, because he knew that the emperor had persecuted the Jews in his empire, but they refused, for which they were thrown from a cliff.

Bulgaria became the dominant power of Southeastern Europe after the Battle of Klokotnitsa. His troops swept into Theodore's lands and conquered dozens of Epirote towns. They captured Ohrid, Prilep and Serres in Macedonia, Adrianople, Demotika and Plovdiv in Thrace and also occupied Great Vlachia in Thessaly. Alexius Slav's realm in the Rhodope Mountains was also annexed. Ivan Asen placed Bulgarian garrisons in the important fortresses and appointed his own men to command them and to collect the taxes, but local officials continued to administer other places in the conquered territories. He replaced the Greek bishops with Bulgarian prelates in Macedonia. He made generous grants to the monasteries on Mount Athos during his visit there in 1230, but he could not persuade the monks to acknowledge the jurisdiction of the primate of the Bulgarian Church. His son-in-law, Manuel Doukas, took control of the Empire of Thessaloniki. The Bulgarian troops also made a plundering raid against Serbia, because Stefan Radoslav, King of Serbia, had supported his father-in-law, Theodore, against Bulgaria.

Ivan Asen's conquests secured the Bulgarian control of the Via Egnatia (the important trade route between Thessaloniki and Durazzo). He established a mint in Ohrid which began to strike gold coins. His growing revenues enabled him to accomplish an ambitious building program in Tarnovo. The Church of the Holy Forty Martyrs, with its facade decorated with ceramic tiles and murals, commemorated his victory at Klokotnitsa. The imperial palace on the Tsaravets Hill was enlarged. A memorial inscription on one of the columns of the Church of the Holy Forty Martyrs recorded Ivan Asen's conquests. It referred to him as the "tsar of the Bulgarians, Greeks and other countries", implying that he was planning to revive the Byzantine Empire under his rule. He also styled himself emperor in his letter of grant to the Vatopedi Monastery on Mount Athos and in his diploma about the privileges of the Ragusan merchants. Imitating the Byzantine emperors, he sealed his charters with gold bulls. One of his seals portrayed him wearing imperial insignia, also revealing his imperial ambitions.
detectable_content:postscript, language:response_language[Spanish]