General Fremont declares martial law in Missouri
August 30, 1861
General Fremont declares martial law in Missouri
In a war effort to rid Missouri of southern sympathizers, and without President Lincoln's knowledge or approval, General Fremont, on August 30, 1861, declared Missouri under martial law and emancipated all slaves belonging to the rebels.
The President ordered Fremont to change the order, but he refused. Lincoln then revoked the order and relieved Fremont of command.
http://www.mr.lincolnandfreedom.org/inside.asp?ID=31&subjectID=3