In the 19th century, before the civil war, they were not allowed to vote at all and had no suffrage rights. After the civil war, they got general suffrage according to the amendments made to the constitution. However, their suffrage was limited by local governments which introduced voting taxes without which you couldn't vote, or literacy tests which african-americans of the time could not pass. In the 20th century, african-american women got their voting rights when the 19th amendment was passed allowing women to vote. They got their full voting rights in the 20th century when things like limiting voting was banned.
