The basilica of Haghia Sophia in Nicaea is the result of multiple phases of development. A number of scholars have dealt with the architecture of the monument and the history of its construction: Brounoff published a rather outdated description and analysis of the building in 1925, Schneider gave two accounts of the excavations he carried out in the church in 1935, Sabine Möllers studied the monument thoroughly in her doctorate thesis in 1994 and Peschlow produced a complete outline of the relevant scientific knowledge in 2001, in the context of a wider presentation of the churches of Nicaea. Based on the information presented in the latter, the original edifice, episcopal church of the city and venue of the seventh Ecumenical Council, was possibly constructed in the fifth or sixth century. The building went through various transformations during the following centuries, the last of which – by the architect Sinan – occurred in the sixteenth century, since the church had been converted into a mosque after the conquest of Nicaea by the Turks in 1331. The most important of the Byzantine repairs of the church have been dated by the aforementioned scholars to the eleventh century, and more specifically to a time soon after the earthquakes which affected Nicaea in the period 1063–1065, causing serious damage to most buildings. The neighbouring church of the Dormition (Koimesis) of the Virgin was also extensively reconstructed at the time, after the partial collapse of its superstructure.