The Bayezid II Mosque is an early 16th century Ottoman imperial mosque located in the Beyazıt Square area of Istanbul, near the ruins of the Forum of Theodosius of ancient Constantinople.
The Beyazidiye Camii was commissioned by Ottoman Sultan Bayezid II, and was the second large imperial mosque complex to be erected in Istanbul after the conquest. As the earliest complex, the Fatih Mosque was subsequently destroyed by earthquakes and completely rebuilt in a different style, the Beyazidiye complex is of considerable historical and architectural significance. That the architect was a nephew of the Greek architect of the Fatih Mosque (Atik Sinan or Christodoulos), is known from a grant of Bayazid II. This grant confirms the endowment by Mehmed II of the Greek orthodox Church of Saint Mary of the Mongols, the only church in Istanbul never converted into a mosque, to the mother of Christodoulos (the Bayezid II Mosque’s architect’s grandmother) in acknowledgment of the two architects’ work. Little else is known about the architect other than that he also built a caravansaray in Bursa; however, the polished style of the mosque itself indicates experience with earlier Ottoman and western architectural techniques. The surrounding külliye complex (madrasah, primary school, imaret (public kitchen) and hammam), date from 1501 to 1506.
The dome was partially rebuilt after an earthquake in 1509, and Mimar Sinan conducted further repairs in 1573–74. The minarets burned separately in 1683 and 1764. An inscription above the courtyard entrance suggests that repairs were also conducted in 1767.