In whose reign did England win the Battle of Blenheim?

The Battle of Blenheim, a significant conflict during the War of the Spanish Succession, was won by the forces allied with England under the command of John Churchill, the Duke of Marlborough, in 1704. This victory was crucial in ensuring the safety and power of England and its allies against French expansionism.

Queen Anne was the monarch at that time, thus her reign is specifically associated with this decisive battle. Her leadership and support of the military campaigns were pivotal in securing this important victory, and the Battle of Blenheim is often seen as a highlight of her rule.

The other figures listed, such as Henry VIII, George II, and Elizabeth I, were rulers of England during different periods and were not connected to the Battle of Blenheim, which occurred long after their reigns. Therefore, Queen Anne is the correct answer as the reigning monarch under whom England triumphed at this historic battle.