I Know Nothing!
Article on the Know-Nothings, some of their prominent members, and their fear that the Vatican planned to take Cincinnati by military force.
Wikipedia: Know-Nothing Movement
Encyclopedia-style article on this nativist movement. Includes the platform of the American Party.
Lause's Links: The American Party
Points out that the party varied from state to state, and suggests that it was fundamentally a Unionist party hoping to combat the Democrats on some other issue than slavery.
The Legacy of the Know-Nothings
For teens. Although this political party didn't last for even ten years, its story can show something about America today.