THEY ARE (IN ORDER OF WHEN THEY ABOLISHED SLAVERY)...
1. PENNSYLVANIA - BANNED SLAVERY IN 1780 (JOINED THE UNION 12-12-1787)
2. MASSACHUSETTS - BANNED SLAVERY IN 1783 (JOINED THE UNON 2-6-1788)
3. NEW HAMPSHIRE - BANNED SLAVERY IN 1783 (JOINED THE UNION 6-21-1788)
4. CONNECTUCUT - BANNED SLAVERY IN 1784 (JOINED THE UNION 1-9-1788)