With the certification of the 19th Amendment to the U.S. Constitution on August 26, 1920, women secured the right to vote after a decades-long fight. "The right of citizens of the United States to vote shall not be denied or abridged by the United States or by any State on account of sex,” it reads.

But while the passage of the 19th Amendment enabled most white women to vote, that wasn’t the case for many women of color.

“For Black women, their votes weren’t lifted by that tide in the South,” Christina Rivers, associate professor of political science at Depaul University, says. “Their votes were suppressed solely on the basis of race.”

Also prevented from voting: Native Americans—both men and women—did not gain the right to vote until the Snyder Act of 1924, four years after the ratification of the 19th Amendment and more than 50 years after the passage of the 15th Amendment. Even then, some Western states, including Arizona, New Mexico and Utah, didn’t grant Native Americans the right to vote until the 1940s and ‘50s. It wasn't until the Cable Act of 1922 that women were allowed to keep their citizenship—and gain the right to vote—if they were married to an immigrant (who had to be eligible to become a U.S. citizen).

In Puerto Rico, literate women won the right to vote in 1929, but it wasn't until 1935 that all women were given that right. And Asian American immigrant women were denied the right to vote until 1952 when the Immigration and Nationality Act allowed them to become citizens.

But even with the passage of these amendments and acts, a number of nefarious methods were used to keep segments of the population from voting. Most of these measures targeted Black Americans in the Jim Crow South, but Hispanic, Native American and Asian Americans also faced obstacles to voting in the Southwest and West.

“When you combine literacy tests, invasive registration forms, interpretation tests, poll taxes and outright violence, this kept Black voting registration percentages down to the single digits in most of the Confederate South,” Rivers says.

In fact, according to Pearl Dowe, professor of political science and African American studies at Emory University, efforts to legalize the right to vote were fraught with racism and division stemming back to the abolitionist movement.

"The biracial coalition that formed during abolition was very tenuous and eventually fractured due to conflicts about what should the status of freed Blacks be," she says. "This was often based on whites having conflicting attitudes about the humanity of Blacks and if they were equal to whites. These issues and divides continued into the suffrage movement."

And those divides didn’t stop with the 19th Amendment’s passage. In addition to threats, intimidation, harassment, beatings and murders, other devices, such as literacy tests, were implemented not only in the Jim Crow South, but also in some other states including Connecticut, and designed specifically to deny Black people and immigrants from voting.

Administered and interpreted arbitrarily, registrars could ask citizens test questions at their discretion and also had the authority to pass or fail applicants with no explanation. The practice didn’t end in some states until the passage of the Voting Rights Act of 1965.

“There’s ample evidence that even if Black people somehow managed to succeed and pass these tests they would still often be denied the right to register to vote and, in some states, it was illegal for registrars to explain why someone was denied the right to vote or why they didn’t ‘pass’ these tests,” Rivers says. “White applicants, including those who only had a second- or third-grade education and were illiterate were not required to take these tests or were only required to answer one or two questions. There’s also evidence of registrars giving them the answers.”

Related to literacy tests were interpretation tests, which weren’t struck down by the courts until the late 1950s on the grounds they were too arbitrary. According to Rivers, an interpretation test would involve transcribing or translating a passage of a complicated piece of writing—usually legalese from a state constitution. “They were designed to be very difficult to pass,” she says.

Another barrier to voting, in existence since the early establishment of America, was the poll tax.

“Poll taxes were very effective in the former Confederate South because most Black folks there were very poor and couldn’t afford that tax,” Rivers says. “The poll taxes were pervasive pretty much from day one, but were ramped up even more in the confederate states.”

Holding all-white primaries and all-white political party memberships were also used to suppress people of color from voting in some Southern states. “Anybody could vote in the general election, but to vote in the primaries you had to be white,” Rivers says.

A series of litigation to strike down all-white primaries took place over several decades. “And each time the Supreme Court would strike something down these states would come up with some other device to replace it,” according to Rivers. “So it was kind of a quasi-disenfranchisement.”

Extremely complicated voter registration was another method used to keep people of color from voting.

“In Alabama, for example, the registration form was four pages long and very, very invasive,” Rivers says. “Filled with questions meant to intimidate, discourage and disqualify applicants, they were pervasive throughout the Jim Crow South.”

It wasn’t until 45 years after the 19th Amendment became law, with the passage of the Voting Rights Act, that all women were free to vote.

“The Voting Rights Act did exactly what it was supposed to do,” Rivers says. “It allowed for the registration and the voting of historically suppressed minorities. It worked very well and in a very short course, Black voting rates and registration numbers skyrocketed.”