The right to vote was originally let to each individual state to choose. Slave owned states decided white men could vote but have their Black slaves be counted when figuring up how many members of Congress each state is entitled to.
This results in the Federal Goverment being able to choose who is a citizen but each states having the power to say who can vote.
Most of the states only allowed white male with certain am out of land to vote. Since only a small minority of white males own enough property to qualify, the great majority of the population is denied the vote. Estimated, less than 5% of the population are eligible to vote in the election of 1800.
This is important in history because this was the start of all the revolt of the suppressed, including immigrants, females, African Americans, and those who cannot afford land.