In the 1860s, supporters for woman suffrage began to pressure Congress for the right to vote. The first woman suffrage amendment was introduced in Congress in 1878, and for the next 40 years it was reintroduced regularly, becoming popularly known as the Susan B. Anthony Amendment.
On May 21, 1919, the House of Representatives passed the amendment, and 2 weeks later, the Senate followed. When Tennessee became the 36th state to ratify the amendment on August 18, 1920, the amendment passed its final hurdle of obtaining the agreement of three-fourths of the states. Secretary of State Bainbridge Colby certified the ratification on August 26, 1920, forever changing the face of the American electorate.
Source: National Archives of The United States of America.
A website to check out is the Women’s Vote Centennial Initiative.