so this historically marks the Sack of Tus in 1220 AD. Gengis Khans son Toloi invades the Khorasan region of Iran or Persia at the time and destroys the city of Tus, slaughtering countless muslims and destroying books, institutes, agricultural land, homes, etc.
the most notable Shi'ite Iranian academic scholar at the time Nasir Al-Din Al-Tusi (Known for the Tusi Couple) managed to escape the siege and get to safety. In this anime, Muhammad is Nasir Al-DIn Al-Tusi