A kusa da 1221-1222 Emperor Ivan Asen II na Bulgaria ya kulla kawance da Theodore Komnenos Doukas, mai mulkin Epirus.Amincewa da yarjejeniyar, Theodore ya yi nasarar cinye Tasalonika daga Daular Latin , da kuma ƙasashe a Makidoniya ciki har da Ohrid, kuma ya kafa Daular Tasalonika.Bayan mutuwar Sarkin Latin Robert na Courtenay a 1228, Ivan Asen II an dauke shi mafi yiwuwar zabi ga regent na Baldwin II.Theodore ya yi tunanin cewa Bulgaria ita ce kawai cikas da ya rage a kan hanyarsa ta zuwa Constantinople kuma a farkon Maris 1230 ya mamaye kasar, ya karya yarjejeniyar zaman lafiya kuma ba tare da sanarwar yaki ba.Theodore Komnenos ya kira babban sojoji, ciki har da sojojin haya na yamma.Yana da kwarin gwiwa cewa zai yi nasara, ya tafi da dukan fadar sarki, har da matarsa ​​da 'ya'yansa.Sojojinsa suna tafiya a hankali suna washe garuruwan da suke kan hanyarsu.Lokacin da sarkin Bulgeriya ya samu labarin cewa an kai wa jihar hari, sai ya tara wasu ‘yan tsirarun sojoji dubu da suka hada da ‘yan Cuman , ya nufi kudu da sauri.A cikin kwanaki hudu mutanen Bulgaria sun yi nisa sau uku fiye da yadda sojojin Theodore suka yi tafiya a cikin mako guda.A ranar 9 ga Maris, sojojin biyu sun hadu a kusa da kauyen Klokotnitsa.An ce Ivan Asen II ya ba da umarnin karya yarjejeniyar kare juna da ta makale a kan mashinsa kuma a yi amfani da shi a matsayin tuta.Ya kasance mai fasaha mai kyau kuma ya sami damar kewaye abokan gaba, waɗanda suka yi mamakin saduwa da Bulgarian nan da nan.Aka ci gaba da gwabzawa har zuwa faduwar rana.An yi galaba a kan mutanen Theodore kwata-kwata, wani karamin runduna ne kawai karkashin dan uwansa Manuel ya yi nasarar tserewa daga fagen fama.An kashe sauran a yaƙin ko kuma aka kama su, har da fadar sarauta ta Tasalonika da Theodore kansa.Nan da nan Ivan Asen II ya saki sojojin da aka kama ba tare da wani sharadi ba kuma an kai manyan mutane zuwa Tarnovo.Shahararrensa na zama mai jinƙai da adalci ya ci gaba da tafiyarsa zuwa ƙasashen Theodore Komnenos da yankunan da Theodore ya yi nasara a kwanan nan a Thrace da Makidoniya Bulgaria ta dawo da su ba tare da juriya ba.