The Ottomans began their expansion into Europe from Anatolia with the capture of Gallipoli in 1354. From here they went on to attack Thrace and secured their first important city, Adrianople, in the 1360s. Adrianople then became their capital until the seat of the Byzantine Empire, Constantinople, was finally taken in 1453. Wallachia accepted the growing power of the Ottoman Empire, becoming a vassal state in 1396. It then gained independence following the Ottoman loss to the Timurid Empire in 1402 but succumbed to Ottoman influence again in 1417. Moldavia, positioned between the powerful kingdom of Hungary and the Ottoman Empire, becoming a vassal of the latter in 1456, although this position changed a number of times. The Balkan kingdoms all rallied fierce resistance against the Ottoman onslaught but eventually fell one by one whilst the fragmented dynamic of the region resulted in many independent pockets of control.
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