Dred Scott was taken by slaveholder John Sanford to the free state of Illinois and to the Wisconsin Territory, which also banned slavery. Awhile later, they returned to Missouri, a slave state. Years later, Dred Scott tried to sue Sanford for his freedom under the Missouri legal principle of "once free, always free." Under Missouri law enslaved people were entitled to freedom if they had lived in a free state at any time. He lost because he was black (slave) and was considered property.