With Texas Gov. Rick Perry sending National Guard troops to the border, look back at the tumultuous history of immigation in America.
1795 -- The Naturalization Act restricts U.S. citizenship to "free white persons" who live in America for at least five years and renounce their allegiance to their former country.
July 23 is National Hot Dog Day! Learn more about the tasty food, from where it originated from to what it's made of.