The Christiana Riot, also known as Christiana Resistance, Christiana Tragedy, or Christiana incident, was the successful armed resistance by free Blacks and escaped slaves to a raid led by a federal marshal to recover four escaped slaves owned by Edward Gorsuch of Maryland. The raid took place in the early morning hours of September 11, 1851, at the house in Christiana, Pennsylvania, of William Parker, himself an escaped slave. This took place after the federal Fugitive Slave Act of 1850 increased penalties for assisting escaped slaves and required state government officials, even in free states such as Pennsylvania, to assist in the recapture of slaves.

The confrontation resulted in an exchange of gunfire, the death of Edward Gorsuch, and the dispersal of the raiders. In the aftermath many of the Blacks involved quickly traveled to the safety of Canada. In total, 41 persons were indicted by the federal government for treason, including both Blacks and Whites. Castner Hanway, a white man from Christiana, was the first to be tried, beginning in November 1851. After only 15 minutes of deliberation by the jury he was acquitted, and charges against the remaining defendants were dropped. The issue became a national lightning rod, and aroused strong sectional sentiment. It was one of many events leading to the American Civil War.