On 23 September 1779, during a Revolutionary War naval battle against HMS Serapis, John Paul Jones refused to surrender his command of the disabled Bonhomme Richard by uttering his famous retort, "I have not yet begun to fight."
On 26 September 1918, Coast Guard Cutter Tampa (under the command of the U.S.. Navy) was sunk off the Bristol Channel by German U-boat 91, resulting in the largest loss of life suffered by U.S. naval forces during WWI.