Final answer:
Oliver Hazard Perry became a national hero for his decisive victory over a British squadron at the Battle of Lake Erie during the War of 1812.
Step-by-step explanation:
The individual who became a national hero for defeating a British squadron in the Battle of Lake Erie during the War of 1812 is Oliver Hazard Perry. This naval victory marked a turning point in the war, with the American forces able to recover control over half the Northwest and opening up territories for settlement. Perry's leadership and courage made him an iconic figure in American history, as his victory helped restore American morale and signaled a resurgence in the war effort against the British and their Native American allies.