1. Prior to May 24, 1934
Before May 24, 1934, the law provided that only fathers could pass U.S. citizenship to their children. The rules were simple: If a U.S. citizen father resided in the United States at some time before the child's birth, the child automatically acquired citizenship. When and for how long the father lived in the United States didn't matter. Technically, a day or a week would be enough if it could be regarded as a residence and not just a visit.
The child didn't have to do anything special to keep his or her U.S. citizenship. These rules also applied to children born outside of marriage if the U.S. citizen father legally legitimated the child at some point.
This law was challenged several times on the grounds that it was discriminatory -- and some courts held that mothers could also pass citizenship to their children. Congress finally addressed the issue in 1994 and amended the law retroactively, providing that either parent could pass U.S. citizenship to children under this law.
Therefore, if you were born before May 24, 1934, and either of your parents was a U.S. citizen, that citizenship might have been passed on to you. Also keep in mind that if one of your parents was born before May 24, 1934, he or she may have acquired U.S. citizenship from his or her parents. That citizenship could have passed to you under laws in existence at a later date. Checking the family tree may be worth your while.
2. May 25, 1934 to January 12, 1941
If you were born between May 25, 1934 and January 12, 1941, you acquired U.S. citizenship at birth if both your parents were U.S. citizens and at least one lived in the United States before you were born. You didn't have to do anything special to keep your U.S. citizenship.
You could also get U.S. citizenship if only one of your parents was a U.S. citizen, as long as that parent lived in the United States at some time. If your U.S. citizenship came from only one parent, you would have been required to reside in the United States for at least two years between the ages of 14 and 28 in order to retain your citizenship. If the one U.S. citizen parent was your father and you were born outside of marriage, the same rules applied if your father legally legitimated you.
3. January 13, 1941 to December 23, 1952
If you were born between January 13, 1941 and December 23, 1952, you automatically acquired U.S. citizenship if both your parents were U.S. citizens and at least one had a prior residence in the United States. You didn't have to do anything special to keep your U.S. citizenship.
If only one parent was a U.S. citizen, that parent must have lived in the United States for at least ten years prior to your birth, and at least five of those years must have been after your parent reached the age of 16. To keep your citizenship, you must have lived in the United States for at least two years between the ages of 14 and 28 (called a residence requirement). However, as a result of a U.S. Supreme Court decision, if you were born after October 9, 1952, your parent still had to fulfill the residence requirement in order to pass citizenship to you, but your own residence requirements for retaining U.S. citizenship were abolished. If your one U.S. citizen parent was your father and you were born outside of marriage, the same rules applied if your father legally legitimated you before your 21st birthday and you were unmarried at the time.
4. December 24, 1952 to November 13, 1986
If, at the time of your birth, both your parents were U.S. citizens and at least one had a prior residence in the United States, you automatically acquired U.S. citizenship with no conditions for retaining it.
If only one parent was a U.S. citizen at the time of your birth, that parent must have resided in the United States for at least ten years, at least five of which had to be after the age of 16. There are no conditions placed on retaining this type of citizenship. If your one U.S. citizen parent is your father and you were born outside of marriage, the same rules apply if your father legally legitimated you before your 21st birthday and you were unmarried at the time. If legitimation occurred after November 14, 1986, your father must have established paternity prior to your 18th birthday, either by acknowledgment or by court order, and must have stated in writing that he would support you financially until your 18th birthday.
5. November 14, 1986 to Present
If at the time of your birth, both your parents were U.S. citizens, and at least one had a prior residence in the United States, you automatically acquired U.S. citizenship with no conditions for retaining it.
If only one parent was a U.S. citizen at the time of your birth, that parent must have resided in the United States for at least five years, at least two of which must have been after the age of 14. You don't need to do anything special to keep this type of citizenship. If your one U.S. citizen parent is your father and you were born outside of marriage, the same rules apply if your father established paternity prior to your 18th birthday, either by acknowledgment or by court order, and stated in writing that he would support you financially until your 18th birthday.
