Final answer:
Nationally, women gained full membership in their union of citizenry with the 19th Amendment in 1919, ratified in 1920, granting them full voting rights.
Step-by-step explanation:
Women gained full union membership in different stages, but nationally the definitive moment was the passage and ratification of the 19th Amendment in 1919-1920, allowing women full voting rights.
The fight for women's rights has involved various strategies, notable figures, and activism. Beginning with the efforts of leaders like Elizabeth Cady Stanton and Susan B. Anthony, the movement saw the merging of different groups into the National American Woman Suffrage Association (NAWSA).
Their persistent efforts cumulated in the successful ratification of the 19th Amendment, despite opposing arguments that suffrage would lead to increased family strife and the degradation of women by exposing them to politics. The victory also showcased the political efficacy of women and the possibility of radical change, as they contended that principles such as 'equal rights for all' should extend to voting rights.