Ulubatlı Hasan, Ottoman commander (born 1428)

Ulubatlı Hasan

Turkish martyr (1390 – 1453)

Ulubatlı Hasan, also known as Baba Hasan Ağa the Standard Bearer or Baba Hasan-ı ‘Alemî, was the sekbanbaşı who erected the first standard on the Byzantine walls during the Conquest of Constantinople.