 Clearly intending to usurp the throne, a new series of civil wars from 1352 to 1357 were eventually won by John V, deposing the Kantakouzenoi.In 1382, the Kantakouzenoi were also driven out of the Morea (the modern-day Peloponnese) and John V's son Theodore was placed to govern it as the semi-independent Despot of the Morea, an important victory as the region was quickly becoming the most important Byzantine province.The Byzantine civil wars, and the collapse of Stefan Dušan's Serbian Empire following his death in 1355, had allowed the Ottoman Turks to expand almost unopposed through the Balkans and in the second half of the 14th century, the empire passed almost without a fight under Ottoman sovereignty, forced to pay tribute and offer military aid if needed.