After this incident and realizing the true nature of life after observing the four sights, Siddhartha left the palace on his horse Katakana, accompanied only by Shanna. He sent Shanna back with his possessions and began an ascetic life, at the end of which he attained enlightenment as Gautama Buddha.
The Louisiana Purchase, which was actually made by Jefferson himself, was a shift in his general principles because it required great power on behalf of the federal government, which Jefferson himself didn't like. The same goes for the Monroe Doctrine.