The Kingdom of Hungary reached one of its greatest extents during the Árpádian kings, yet royal power was weakened at the end of their rule in 1301. After a destructive period of interregnum (1301–1308), the first Angevin king, Charles I of Hungary – a bilineal descendant of the Árpád dynasty – successfully restored royal power, and defeated oligarch rivals, the so-called "little kings". The second Angevin Hungarian king, Louis the Great (1342–1382), led many successful military campaigns from Lithuania to Southern Italy (Kingdom of Naples), and was also King of Poland from 1370. After King Louis died without a male heir, the country was stabilized only when Sigismund of Luxembourg (1387–1437) succeeded to the throne, who in 1433 also became Holy Roman Emperor. Sigismund was also (in several ways) a bilineal descendant of the Árpád dynasty.