Final answer:
An expedition into Mexican territory is NOT an event that led to the War of 1812. The conflict was mainly caused by issues with Great Britain involving trade control, impressment of sailors, and tensions over territory with Native Americans and Canada. The correct option is A.
Step-by-step explanation:
The event that is NOT an event that led to the War of 1812 is a) expedition into Mexican territory. The War of 1812 was primarily prompted by Great Britain's attempt to control trade through economic warfare, supporting expeditions into Native American territory, and America's desire to control Canadian territory.
Great Britain's practices, such as the impressment of American sailors, the supply of arms to Native fighters, and the failure to abandon posts in the Northwest Territory as required by Jay's Treaty, were among the factors that provoked the war.
In contrast, expeditions into Mexican territory were not associated with the lead up to the War of 1812, as the issues with Mexico became prominent later, particularly with the Mexican-American War (1846-1848), long after the War of 1812 had ended.