Who was Abraham Lincoln's vice president during his first term?

Abraham Lincoln's vice president during his first term was Hannibal Hamlin.

Hamlin, a senator and former Democrat from Maine, joined the newly formed Republican Party in 1856 because of his opposition to slavery's expansion. The 1860 Republican ticket paired him with Lincoln, an Illinois politician, balancing the ticket geographically and politically. They took office on March 4, 1861, as the secession crisis rapidly escalated into the Civil War.

Hamlin was the 15th vice president and served from 1861 to 1865. He supported major wartime measures, including emancipation and the use of Black troops, but the vice president then had limited influence in the executive branch and did not regularly attend cabinet meetings.

A common mix-up is Andrew Johnson, who became Lincoln's vice president for the second term. The 1864 Republican ticket, reorganized as the National Union ticket, replaced Hamlin with Johnson, a pro-Union Democrat from Tennessee. Hamlin's term ended on March 4, 1865, when he presided over Johnson's swearing-in.