Encouraged by the results of the 13th and 14th amendments, the U.S Congress found the strength to resist further discriminations against African-Americans. For instance, after President Abraham Lincoln was assassinated, his replacement, President Andrew Johnson announced that only whites could take part in conventions to rewrite southern constitutions. Congress in response passed a civil rights bill in 1866 to prevent this. Johnson tried to stop Congress from passing this bill, but he was unsuccessful. Then, there was Congress’s response to the Black Codes, state laws passed by Southerners to make it hard for African-Americans to be able to vote, once the Reconstruction was over. The 15th amendment to the U.S. Constitution was passed to address these Black Codes, stating that the government could not deny any citizen the right to vote because of their race, color, or if in the past they were a slave. This amendment further ensured the right of African-American men to vote. The time it took for African Americans to acheive equality was about 107 years (13th amendment to equal rights amendment) but this great turning point changed greatly how the people of the U.S.A. treat African Americans.