Since 1787, changes have been made to the United States Constitution 27 times by amendments (changes). The first ten of these amendments are together called the Bill of Rights. When it was signed in 1787, the Constitution had a preamble and seven main parts, called articles.
The 15th Amendment— which was passed by Congress on February 26, 1869, and ratified on February 3, 1870 — guarantees the right to vote and guarantees that right cannot be denied based on race.
