Dred Scott, a slave, was taken by his master to the free territories of Illinois and Wisconsin. He proceeded to work on the free land for several years under his master. His master eventually returned with him to Missouri, a slave state, where the master died. Scott then decided to sue for his freedom, claiming that he deserved it because he lived on free land for so long. The case made is way up to the United Sates Supreme Court, where it was declared that he could not be free and that no slave of descendent of slave could not, or ever be, a US citizen. This ruling affected not only Scott but also nearly 4 million slaves living in America at the time.