Battle of Klokotnitsa The Battle of Klokotnitsa ( , " Bitkata pri Klokotnitsa " ) occurred on 9 March 1230 near the village of Klokotnitsa ( today in Haskovo Province , Bulgaria ) . As a result , the Second Bulgarian Empire emerged once again as the most powerful state in Eastern Europe and the power of the Despotate of Epirus faded . The battle is often considered by historians to be the luckiest and most fruitful in Bulgarian military history . Origins of the conflict . Around 1221 – 1222 the Bulgarian Emperor Ivan Asen II made an alliance with Theodore Komnenos Doukas of Epirus . Secured by the treaty , Theodore managed to conquer Thessalonica from the Latin Empire , as well as Bulgarian lands in Macedonia including Ohrid . After the death of the Latin emperor Robert of Courtenay in 1228 , Ivan Asen II was considered the most probable choice for regent of Baldwin II . Theodore thought that Bulgaria was the only obstacle left on his way to Constantinople and in the beginning of March 1230 he invaded the country , breaking the peace treaty and without a declaration of war . The battle . Theodore Komnenos summoned an enormous army including western mercenaries . He was so confident for his victory that he took the whole royal court with himself including his wife and children . His army moved slowly and plundered the villages on its way . When the Bulgarian tsar learned that the state was invaded , he gathered a small army of a few thousand men and quickly marched southwards . For four days the Bulgarians covered a distance three times longer than Theodore ' s army for a week . On 9 March , the two armies met near the village of Klokotnitsa . It is believed that Ivan Asen II ordered the broken mutual protection treaty to be stuck on his spear and used as a flag . He was a good tactician and managed to surround the enemy who was surprised to meet the Bulgarians so soon . The battle continued until sunset . The Epirotians were completely defeated , only a small force under the despot ' s brother Manuel managed to escape the battlefield . The rest were killed in the battle or captured , including the royal court of Epirus and Theodore himself . Ivan Asen II ' s Tarnovo Inscription . In order to commemorate the battle , the Bulgarian emperor had an inscription carved in one of the marble columns of the Church " Holy Forty Martyrs " in the capital of the Bulgarian empire Great Tarnovo . Among all existing documents the text of this inscription is the most accurate evidence of the outcome and the aftermath of the battle : " " In the year 6738 ( 1230 ) , third indiction . John Asen in God Christ true Tsar and sovereign of the Bulgarians , son of the old Tsar Asen , raised from the foundations and decorated with art this holy church in the name of the Holy 40 Martyrs , with the help of whom in the twelfth year of my reign when this temple was being decorated . I made war in Byzantium and defeated the Greek army and captured their Tsar , Kyr Teodore Komnenos , together with all his bolyar s . And I occupied all of his land from Odrin ( Adrianople ) to Drach ( Dyrrhachium ) , Greek and also Albanian and Serbian ; and the towns around Constantinople and this very town were ruled by the Frizes ( Latins ) , but they also subjugated to my empire ; because they had no other Tsar but me and thanks to me they spent their days , because God ordered this , because without Him neither a deed , nor a word is done . Glory to Him forever , amen . " " Aftermath . Ivan Asen II immediately released the captured soldiers without any conditions and the nobles were taken to Tarnovo . His fame for being a merciful and just ruler went ahead of his march to the lands of Theodore Komnenos and they were regained to Bulgaria without resistance .