Born in Virginia, Scott first lived in Missouri in about 1830, when the Peter Blow family emigrated to St. Louis. He was sold by Blow to Dr. John Emerson, an Army surgeon, and began his trek to freedom when Emerson took him to Rock Island, Illinois, in 1833. Several years later, Scott married Harriett Robinson Scott at Fort Snelling, Minnesota Territory.
In 1846, Scott and his wife filed separate petitions in St. Louis Circuit Court, seeking their freedom according to a Missouri law which had long acknowledged that slaves taken to free territory were entitled to their freedom. They lost their first trial in 1847; but the court granted a new trial. After some maneuvering in the appeals courts, the case again went to trial in 1850. The Scotts won. However, the Missouri Supreme Court, speaking through a 2-1 majority, reversed years of precedent in holding that the Scotts were not free as a result of years residing in free territory.
The case which produced the infamous 1857 decision of the United States Supreme Court was commenced in federal court in St. Louis in 1854, and sought to use federal law to override the Missouri Supreme Court decision.
The Scotts were freed through the intervention of the Blow family, two months after the U.S. Supreme Court decision. Dred Scott passed away about a year later.