Which event defined Madison's presidency? Meaning which event was most important during his time in the office?

End of the War of 1812

News arrives of the December 1814 Treaty of Ghent that ends the War of 1812. On February 15, Congress appropriates $500,000 for the reconstruction of federal buildings. The Senate ratifies the Treaty of Ghent on February 16.

the apollo program, also known as project apollo, was the third united states human spaceflight program carried out by the national aeronautics and space administration (nasa), which succeeded in landing the first humans on the moon from 1969 to 1972.