1800 – Congress Reduces Naturalization Residency Requirements to Five Years

“[T]he Alien Act was not without effect, causing protests among various
ethnic groups, especially the Irish. When he was elected president in
1800, due in no small part to the immigrant vote, Jefferson wanted to
get rid of the residency requirement. Congress, believing residency was
still a key element of citizenship, only lowered the requirement to the
previous length of five years.”