Complex sentence: He was ruler of both the Spanish Empire from 1516 and Holy Roman Empire from 1519, as well as of Habsburg Netherlands from 1506, until he voluntarily stepped down from these and other positions by a series of abdications between 1554 and 1556.
Split into simpler sentences: He was ruler of both the Spanish Empire from 1516 and the Holy Roman Empire from 1519, as well as of Habsburg Netherlands from 1506. He voluntarily stepped down from these and other positions by a series of abdications between 1554 and 1556.