 There are several references to the cathedral in medieval sources . The earliest reference to the church tells of the transfer of Saint Michael the Warrior 's relics from the Potuka fortress to the Patriarchal Cathedral on the order of Tsar Kaloyan ( r . 1197 – 1207 ) . The housing of a warrior saint 's relics in the Patriarchal Cathedral signifies the incessant warfare against Byzantines and Latins that dominated Kaloyan 's reign . In the late 14th century , the last Patriarch of Tarnovo , Saint Evtimiy , described the church as the " great patriarch 's Cathedral of the Holy Ascension " in his writings . 
 <a href='dey_it' title='1'><mark>There</mark></a> are several references to the cathedral in medieval sources . The earliest reference to the church <a href='uninflect' title='2'><mark>tells</mark></a> of the transfer of Saint Michael the Warrior <a href='null_genetive' title='3'><mark>'s</mark></a>relics from the Potuka fortress to the Patriarchal Cathedral on the order of Tsar Kaloyan ( r . 1197 – 1207 ) . The housing of a warrior saint <a href='null_genetive' title='4'><mark>'s</mark></a>relics in the Patriarchal Cathedral <a href='uninflect' title='5'><mark>signifies</mark></a> the incessant warfare against Byzantines and Latins <a href='null_relcl' title='6'><mark>that</mark></a>dominated Kaloyan <a href='null_genetive' title='7'><mark>'s</mark></a>reign . In the late 14th century , the last Patriarch of Tarnovo , Saint Evtimiy , described the church as the " great patriarch <a href='null_genetive' title='8'><mark>'s</mark></a>Cathedral of the Holy Ascension " in his writings . 
It is several references to da cathedral in medieval sources . The earliest reference to the church tell of the transfer of Saint micheal the Warrior  relics from tdaPotuka fortress to thdaatriarchal Cathedral on thedader of Tsar Kaloyan ( r . 1197 – 1207 ) . The housing of a warrior saint  relics in the Patriarchal Cathedral signify the daessant warfare against Byzantines and Latins dominated Kaloyan  reign . In the late 14th century , the lda Patriarch of Tarnovo , Saint Evtimiy , described the church as the " great patriarch  Cathedral of the Holy Ascension " in his writings .