Final answer:
Andrew Jackson is the former US president who fought in the War of 1812, leading to his rise in national prominence and eventual presidency.
Step-by-step explanation:
The former US president who fought in the War of 1812 was Andrew Jackson. This conflict, often termed the Second War of American Independence, saw the United States pitted against Great Britain over issues including impressment of sailors, territorial disputes, and the desire for respect of American sovereignty. Jackson's role as a military leader during the war, particularly his victory at the Battle of New Orleans, propelled him into the national spotlight and helped launch his political career, eventually leading him to the presidency. The War of 1812 officially ended with the Treaty of Ghent, but it was Andrew Jackson's post-war triumph that was seen as a defining moment of American resilience and military capability.