The early sultans after the conquest of Constantinople–Mehmed II, Bayezid II, Selim I and Suleiman I–staunchly maintained that they were Roman emperors and went to great lengths to legitimize themselves as such. Greek aristocrats, i.e. former Byzantine nobility, were often promoted to senior administrative positions and Constantinople was maintained as the capital, rebuilt and considerably expanded under Ottoman rule. The administration, architecture and court ceremonies of the early post-1453 Ottoman Empire were heavily influenced by the former Byzantine Empire.