When did they pass the 15th amendment?

The 15th Amendment to the United States Constitution was proposed in Congress on 26 February 1869 in the last days of the presidency of Andrew Johnson (17th President, Democrat, 15 April 1865 - 4 March 1869) and ratified on 3 February 1870 under the presidency of Ulysses S. Grant (18th President, Republican, 4 March 1869 - 4 March 1877).