2. The Trent Affair (1861)
In November 1861, during the American Civil War, Captain Charles Wilkes of the Union Navy intercepted the British mail steamer Trent and seized two Confederate diplomats, James Mason and John Slidell, who were en route to Europe to seek support for the Confederacy. This action violated British neutrality and nearly led to war between the United States and Great Britain. After diplomatic negotiations, the envoys were released, averting conflict (history.com).
