Sultan Murad II (1421-51) again took up arms against him, and invaded
Serbia as far as Kru[)s]evac.

At the death of Stephen (Lazarevi['c]), in 1427, he was succeeded as
_Despot_ by his nephew, George Brankovi['c]; but the Sultan, claiming
Serbia as his own, immediately declared war on him. The Serbian ruler had
to abandon Belgrade to the Magyars, and Nish and Kru[)s]evac to the Turks.
He then built and fortified the town of Smederevo (or Semendria) lower
down on the Danube, in 1428, and made this his capital. He gave his
daughter in marriage to the Sultan, but in spite of this war soon broke
out again, and in 1441 the Turks were masters of nearly the whole of
Serbia. Later George Brankovi['c] made another alliance with Hungary, and
in 1444, with the help of John Hunyadi, defeated the Turks and liberated
the whole of Serbia as far as the Adriatic, though he remained a tributary
of the Sultan. The same year, however, the Magyars broke the treaty of
peace just concluded with the Turks, and marched against them under their
Polish king, Ladislas; this ended in the disastrous battle of Varna, on
the Black Sea, where the king lost his life. In 1451 Sultan Murad II died
and was succeeded by the Sultan Mohammed. In 1453 this sultan captured
Constantinople (Adrianople had until then been the Turkish capital); in
1456 his armies were besieging Belgrade, but were defeated by John
Hunyadi, who, unfortunately for the Serbs, died of the plague shortly
afterwards. George Brankovi['c] died the same year, and at his death
general disorder spread over the country. The Turks profited by this,
overran the whole of Serbia, and in 1459 captured Smederevo, the last
Serbian stronghold.

Meanwhile Bosnia had been for nearly a hundred years enjoying a false
security as an independent Serb kingdom. Its rulers had hitherto been
known by the title of _Ban_, and were all vassals of the King of Hungary;