In 1860, the second Republican National Convention resulted in the nomination of Abraham Lincoln for President for which Lincoln was elected the 16th President and the first Republican President. The Republican Party was now in control of the national government and many of the southern states, seeing the writing on the wall, seceded to protect their institution of slavery. Following the Presidential Inauguration, Newly elected President Lincoln went to Congress and asked for military funding for 75,000 troops to bring those states back into the United States and as a deterrence of further secessions. Of course, this failed and the United States underwent the bloodiest war in its history.

While the Civil War raged and the Republicans were in control of Washington, D.C., civil rights battles were also engaged and the Republicans led the way. Before the end of the war, President Lincoln had signed the Emancipation Proclamation and congress had authored the 13th amendment to the US Constitution.

The radical Republicans wanted to punish the South for seceding and for the reprehensible institution of slavery. President Lincoln wanted to heal the country so much so that in the election of 1864, he chose a Democrat from Tennessee as his running mate. Andrew Johnson became the Vice-President and succeeded President Lincoln following the assassination.