to the metropolis as a whole, but Stamboul to refer to the central parts located on the historic peninsula, i.e. Byzantine-era Constantinople inside the walls. Islambol The name Islambol ( ) appeared after the Ottoman conquest of 1453 to express the city's new role as the capital of the Islamic Ottoman Empire. It was first attested shortly after the conquest, and its invention was ascribed by some contemporary writers to sultan Mehmed II himself. Some Ottoman sources of the 17th century, most notably Evliya Çelebi, describe it as the common Turkish name of the time. Between the late 17th and late 18th centuries, it was also in official use. The first use of the word "Islambol" on coinage was in 1730 during the reign of sultan Mahmud I. The term Kostantiniyye still appeared, however, into the 20th century. Other Ottoman names Ottomans and foreign contemporaries, especially in diplomatic correspondence, referred to the Ottoman imperial government with particular honorifics. Among them are the following: Bāb-i ʿĀlī (, "The Sublime Porte"); A metonym referring to the gate of Topkapı Palace. Der-i Devlet ( "Abode of the State") Der-i Saʿādet ( "Abode of Felicity" or "Abode of Eudaimonia") Āsitāne ( "Threshold"), referring to the imperial court, a Farsi-origin word spelled in English as Asitane or Asitana. Pāy-taḫt or sometimes Pāyitaḫt (, "The Seat/Base of the Throne") The "Gate of Felicity", the "Sublime Gate", and the "Sublime Porte" were literally places within the Ottoman sultans' Topkapı Palace, and were used metonymically to refer to the authorities located there, and hence for the central Ottoman imperial administration. Modern historians also refer to government by these terms, similar to the popular usage of Whitehall in Britain. The sublime Gate is not inside Topkapı palace; the administration building whose gate is named Bâb-ı Âlî is between Agia Sofia and Beyazit mosque, a huge building. Historical names in other languages Many peoples neighboring the Byzantine Empire used names expressing concepts like "The Great City", "City of the Emperors", "Capital of the Romans" or similar. During the 10th to 12th century Constantinople was one of the largest two cities in the world, the other being Baghdad. Old Norse The medieval Vikings, who had contacts with the Byzantine Empire through their expansion through eastern Europe (Varangians), used the Old Norse name Miklagarðr (from mikill 'big' and garðr 'wall' or 'stronghold') as seen in the Icelandic sagas. This name lives on