King Charles V of Spain gained control of the Habsburg empire in 1519. This event occurred through inheritance from his paternal grandparents, the Habsburg monarchs. Charles V inherited the title of Holy Roman Emperor, ruling over vast territories in Europe including Spain, the Low Countries, and parts of Italy.
This acquisition of the Habsburg empire significantly expanded Charles V's influence and power in Europe, making him one of the most powerful monarchs of his time. His rule was marked by conflicts and alliances with other European powers, particularly during the time of the Protestant Reformation.
Therefore, the correct answer to the question is the Habsburg empire.
