In the early years of American politics it was the Federalists who held power in the new American executive and Congress. The Federalists feared the inflow of new immigrants into America were placing them at a political disadvantage. Since most new immigrants were European and had fled tyrannical governments their politics were Republican.

At the time US Citizenship only had a two year residency requirement. The Federalists in response to this nature of immigration extended the residency requirement to five years and then in 1798 to fourteen years. (more)
Cam Riley: South Sea Republic. Freedom, liberty, equity and an Australian Republic.