Abraham Lincoln originally had planned for emancipation to begin in the loyal slave states, with slaveholders gradually freeing their slaves over the remainder of the nineteenth century and being compensated with financing provided by the federal government. (And as many ex-slaves as possible then emigrating to some ill-defined tropical destination.) Lincoln tried to sell this plan during the first half of 1862, but because of strong resistance among slaveholders in the loyal states of Delaware, Kentucky, Maryland, and Missouri, formal emancipation began in the Confederate South with the Emancipation Proclamation. The disloyalty of slaveholders gave Lincoln, he believed, the power to free slaves in the rebellious states by decree as a war measure using his powers as commander-in-chief. These powers, he also believed, did not extend to the loyal slave states because they were not in rebellion. If freedom was to come to these states, short a federal constitutional amendment, it would have to come from these states themselves.
And on November 1, 1864, Maryland was the first of the loyal slave states to end slavery on its own accord. Getting to that point had not been an easy process. It was given a head start of sorts by the fact Maryland’s slave-based economy had been in decline for decades before the Civil War. Maryland’s farmers long had been making the shift from tobacco, which was suitable for a slave workforce to cereal grains, which were not. The state’s slaveholders had responded to their now surplus workforce either by freeing slaves or (more often) selling them into the internal slave trade (which meant they generally ended up in the cotton states). But a result of the crop shift was that by the eve of the Civil War, the 1860 Census revealed about half of Maryland’s African-American population already was free.
What decades of tobacco’s decline had started, the Civil War accelerated by placing pressures on the peculiar institution which Maryland’s slave system found itself unable to cope with. First, Union troops from the free states entered Maryland over the war’s course, often staying in the state for extended periods, and providing protection in their camps from recapture to numerous slaves, often in return for the fugitives acting as temporary servants. Second, when slavery ended in the District of Columbia in Spring 1862, it became a new sanctuary for Maryland slaves, especially after the repeal of the Fugitive Slave Act in June 1864. Third, the advent of black recruitment into the Union army in 1863, led to thousands of slaves leaving their plantations and gaining their freedom in federal ranks. The collective result of these events and the general weakening of state enforcement of slavery brought on by Civil War caused the price of slaves in Maryland to plummet as many owners sought to sell their human property while they still could, but found few buyers.
Still, some slaveholders continued to resist emancipation and two important bulwarks of slavery hung on in Maryland, in the southern counties and the Eastern shore. Both areas tended to be away from areas where either Union or Confederate forces routinely operated, and the plantation economy there was as robust as anywhere in the state. Slaveholders also had remained politically powerful in the state, even as slavery was in gradual decline before the Civil War. They had managed to enshrine the peculiar institution into the state’s constitution in 1851, meaning that any state-based effort to end slavery in Maryland would require a new state constitution.
The impetus for just such a new constitution came as the Civil War led the political power of the state’s slaveholders to go into decline. The war represented an opportunity for long marginalized anti-slavery forces to assert themselves. Interests that saw Maryland’s future in non-slave-based agriculture and manufacturing, and in growing commercial ties with the North and overseas. With many Maryland Democrats either having gone south to join the Confederacy or their political activities curtailed by Lincoln’s administration and the Union army, which believed Maryland must be held inside the Union by all means, a pro-Union political movement arose in the state during the Civil War under the leadership of future governor, Thomas Swann. It was Swann, who in 1863, pushed the Union party to embrace immediate abolition as a political goal.
With the support of the Union party, which dominated Maryland’s politics after 1863, the new state constitution, which included a ban on slavery, was put up to a referendum on October 12-13, 1864. The vote to approve the constitution was close, in an election marked by charges of intimidation and fraud, and the proposed constitution likely would have lost, but for Maryland’s Union soldiers who were allowed to vote in the field and overwhelmingly supported ending slavery. With the referendum narrowly approved it went into effect on November 1, 1864, 15o years ago today.
Civil War Emancipation 
Excellent article. Thank you very much!