A State Constitutional Convention was held on April 27, 1864, during which a new constitution was written, outlawing slavery in Maryland. This was the first time a state south of the Mason-Dixon line abolished slavery by a vote of the people. When put to a public referendum, the people voted against it, but when the ballots of the soldiers in the field were counted, the vote swung the other way, and the constitution was ratified by a mere 375 vote margin. The new constitution took effect on November 1st after being signed by Governor Bradford. Emancipation Day was first officially recognized in 2013.