It took 72 years!!
The woman suffrage movement actually began in 1848, when a women's rights convention was held in Seneca Falls, New York. ... Thus, over time women began to realize that in order to achieve reform, they needed to win the right to vote.
Beginning in the 1800s, women organized, petitioned, and picketed to win the right to vote.
By 1916, almost all of the major suffrage organizations were united behind the goal of a constitutional amendment. When New York adopted woman suffrage in 1917 and President Wilson changed his position to support an amendment in 1918, the political balance began to shift.