Some 150 years since Abraham Lincoln outlawed slavery in the U.S., a collection of rare Civil War-era photographs have been brought to life through painstaking colorization. February 1 marks National Freedom Day, honoring the signing by President Lincoln of a resolution which became the 13th Amendment to the Constitution and abolished slavery. The photographs, seen here, depict the battle-weary men who fought in the bloody conflict between 1861 and 1865, either for the survival of the Union or a strike out into independence for the Confederates. Scroll down for video An undated Civil War-era picture of Union Army provost marshals - During the Civil War, these were the military police in charge of keeping order among both soldiers and civilians. They often went after deserters or civilians suspected of disloyalty
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February 1 marks National Freedom Day, honoring the signing by President Lincoln of a resolution which became the 13th Amendment to the Constitution and abolished slavery
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The Northern states, led by Lincoln were known as the Union, while the Southern states, the Confederates of America, marched behind Jefferson Davis
Drummer boys, who were often very young, played an important role in the @placeholder - as officers’ orders were given as a series of drumbeats during battle so they could be heard above the noise and confusion