Captain Charles Wilkes, commanding the Union frigate San Jacinto, seizes from the neutral British mail steamer Trent on November 8, 1861, two Confederate commissioners, James Murray Mason and John Slidell (law partner of Confederate Attorney General Benjamin) who seek the support of England and France for the cause of the Confederacy.

This unauthorized seizure sparks a storm of indignant protest from the pro-Confederate British aristocracy, which sympathizes with the southern plantation owners.

Commercial interests, which hope for cheaper raw materials, especially cotton, from an independent South, begin pro-war agitation.

The British government issues an ultimatum demanding an American apology and the release of Mason and Slidell.