Two contemporaneous clergymen, Roger of Torre Maggiore and Thomas the Archdeacon, recorded that Kadan (a son of Ögödei, Great Khan of the Mongols) broke into Bulgaria in March 1242.
Dua rohaniwan kontemporer, Rogerius dari Torre Maggiore dan Thomas Archidiaconus, mencatat bahwa Kadan (putra Ögödei, Khan Agung dari Mongol) masuk ke Bulgaria pada bulan Maret 1242.