Dear Ms. Warmsley,
Thank you for posting your request on History Hub!
Unfortunately, your grandmother, Mary Tasker, lost her United States citizenship due to her marriage to a foreign alien. In March of 1907, Congress passed the Expatriation Act, which decreed, among other things, that female U.S. Citizens who married non-citizens were no longer Americans. This law did not apply to male U.S. Citizens who married foreign women. It was not until the Cable Act of 1922 (also known as the Married Women’s Independent Nationality Act) that former immigration laws regarding marriage were reversed.
After 1922, a woman who had lost her American citizenship could go through the process of repatriation or pursue naturalization. Both kinds of records would appear in the Records of District Courts of the United States (Record Group 21) held at a NARA facility. Please see the National Archives Court Records website to determine which NARA facility has the records for the Federal court in the geographic area where your grandmother Mary resided.
We hope this is helpful. Best of luck with your family research!
[Information provided by Elizabeth Burnes, Subject Matter Expert]