When the United States purchased me. I almost doubled the country's size. What am I?

The Louisiana Territory

Explanation:

When the Thomas Jefferson purchased the Louisiana territory in 1803, it nearly doubled the the country's size.

I think it's Louisiana that was bought and almost doubled the size. Because in 1803, the United States nearly doubled in size when it bought the Louisiana Territory in a deal that shaped history.

Hope this helps :)

there are more but this is what i can come up

new york- english

new orleans- french

new hampshire- english

new mexico- spanish

new jersey- english

this is a good question! i'll do some research and come back when i have the answer!