The Marais des Cygnes Massacre was a shocking event of violence that took place during the Bloody Kansas Period, just before the American Civil War took place. The 1858 event involved the Georgian native, Missouri proslavery leader, Charles Hamilton, and 11 of free-state men that he has captured along with his men.

The horrifying event took place in what is known today as the Marais des Cygnes Massacre Site. Here, five of the 11 men died with Hamilton taking the first shot.

The Marais des Cygnes Massacre Site is now under the care of the Kansas Historical Society. It includes a 19th century fort and house built at the site after the incident. It is also a registered National Historic Landmark.