Born in Harrington, Delaware as Anna L. Melvin, she married George Arniel of Canada and was widowed in 1910.

Annie played a key role in helping to win the women's vote in the United States.

Arniel was a factory worker, living in downtown Wilmington, Delaware, when she was recruited by Mabel Vernon and Alice Paul for membership in the National Woman's Party (NWP).

As a member of the Silent Sentinels she was among the first six suffragists arrested and jailed on June 27, 1917, at the White House.

After participating in a demonstration at the United States Capitol in October 1919, Arniel was "so brutally treated by the police that she was rendered unconscious and her back was injured.