 He fought the Hungarian Kingdom, the Polish Kingdom and the Ottoman Empire, with success, for the most part of his rule.Stephen III was succeeded by increasingly weaker princes, and in 1538 Moldavia became a vassal of the Ottoman Empire, to which it owed a percentage of the internal revenue, that in time rose to 10%.Moldavia was forbidden to have foreign relations to the detriment of the Ottoman Empire (although at times the country managed to circumvent this interdiction), but was allowed internal autonomy, including sole authority over foreign trade.