The term "Flotilla" ("small fleet") has been variously used to designate a group of ships since the earliest years of the United States Navy. During the War of 1812, Commodore MacDonough's Flotilla was victorious in the Battle of Lake Champlain on 11 September 1814. At the outset of the Civil War the Northern naval force consisted of ninety vessels of various descriptions, most of which were too old to be fit for service. It became necessary to improvise a navy immediately, and by 1864, there were over six hundred vessels in commission, and there were over fifty thousand men afloat. The operations of the Federal naval forces were so widely separated that it became necessary to create separate fleets and squadrons, which were designated respectively as the Potomac Flotilla, North Atlantic Squadron, South Atlantic Squadron, East Gulf Squadron, West Gulf Squadron, Mississippi Flotilla, and the Cruising Fleets.
The "Great White Fleet" sent around the world by President Theodore Roosevelt from 16 December 1907 to 22 February 1909 consisted of sixteen new battleships of the Atlantic Fleet, along with a "Torpedo Flotilla" of Destroyers. During the Second World War, the term "Task Flotilla" was used to designate groups of ships assigned specific missions.
In 1973 a major reorganization of the Navy's cruiser-destroyer force resulted in the redesignation Cruiser-Destroyer Flotillas [CRUDESFLOT] as Cruiser-Destroyer Groups (CRUDESGRU). While the term "Flotilla" remains in use to designate a unit composed of several squadrons by a number of other navies around the world, such as the United Kingdom, Japan and Russia, it is no longer used by the US Navy.
The Coast Guard Auxiliary is the civilian volunteer arm of the United States Coast Guard - 35,000 men and women who donate their time and expertise to support the Coast Guard and improve boating safety. The basic unit of the organization is the flotilla, consisting of ten or more boats and presided over by an elected civilian with the title of Flotilla Commander.