Robert E. Lee, the Confederacy’s most respected commander, surrendered only his Army of Northern Virginia to Union Gen. Ulysses S. Grant. Several other Confederate forces—some large units, some small&madsh;had yet to surrender before President Andrew Johnson could declare that the Civil War was officially over.

Why was Grant called unconditional surrender?

In addition to this ultimate success, he won several other campaigns as a general in the Civil War and later served as President between 1869 and 1877. He gained the nickname of “Unconditional Surrender” Grant in 1862 for his response to Confederate overtures at the Battle of Fort Donelson, quoted above.

How did Grant surrender to Vicksburg?

When two major assaults against the Confederate fortifications, on May 19 and 22, were repulsed with heavy casualties, Grant decided to besiege the city beginning on May 25. After holding out for more than forty days, with their supplies nearly gone, the garrison surrendered on July 4.