Charles V, Holy Roman Emperor, ruled from 1519 to 1556 and was a significant figure in European history. He was born in 1500 and inherited a vast empire that included territories in Spain, the Netherlands, and Austria. His reign was marked by conflicts with France and the Ottoman Empire, as well as the challenges posed by the Protestant Reformation. As emperor, Charles sought to maintain Catholic unity in Europe and faced opposition from Protestant leaders like Martin Luther. He convened the Diet of Worms in 1521 to address these issues. Ultimately, he abdicated in 1556, dividing his empire between his brother Ferdinand I and his son Philip II of Spain.