Vermont Abolishes Slavery Vermont is the first of the thirteen colonies to abolish slavery and enfranchise all adult males. See the Source New York Enfranchises Free Propertied Men New York enfranchises all free propertied men regardless of color or prior servitude. See the Source Vermont Republic Becomes First US Territory to Abolish Slavery In its newly ratified constitution, the Vermont Republic becomes the first territory that is now part of the United States to outlaw slavery. See the Source