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CONVOYS. Employed from classical antiquity for the secure passage of land and seaborne commerce, as well as for passage of migrant peoples and fighting forces through hostile regions, convoys proved of signal importance during the European penetration of Africa, the Orient, and the Americas. The maritime convoy system of medieval England, which emerged early in the thirteenth century, afforded the model, providing armed escort vessels for both the cross-Channel wool trade and troop transports bound for beleaguered Calais and Bordeaux.

Early in the conquest of America, Spain employed close escorts and support forces to safeguard its homeward-bound treasure galleons. It established a compulsory convoy system in 1543, enabling the merchants of Seville to dispatch a flota ("fleet") of thirty to ninety merchantmen twice annually to the West Indies, thereby frustrating repeated attacks by British and French freebooters. The Armada of 1588 itself represented a classic prefigurement of the modern troop convoy.

Subsequent English overseas expansion rested not only on mercantile enterprise, an emergent Royal Navy, and deliberate nurture of the colonial system through the Navigation Acts, but also on resolute enforcement of

the convoy acts, dating from 1650, that regulated the organization of convoys and required the arming of merchantmen. Throughout its conflict with France from 1674 to 1815, England refined—notably in the Compulsory Convoy Act of 1798—the complex operation of its ocean and coastal convoy systems. During the American Quasi-War with France (1798–1800), U.S. frigates escorted British convoys in the Caribbean; less than fifteen years later those frigates, abetted by privateers, attacked British transatlantic convoys with but limited success.

With the establishment of the Pax Britannica, the vital role of convoys rapidly diminished. Notwithstanding the virtual disintegration of the American merchant marine during the Civil War, the British Admiralty in 1872 acquiesced in abolishing the Compulsory Convoy Act, relying thereafter on naval patrol of threatened sea routes. That policy proved disastrously ineffective during World War I against commerce-raiding German U-boats. Not until May 1917, when shipping losses threatened Britain with imminent starvation and U.S. escort vessels became available, did the Admiralty reinstitute convoys. The vast shipping control system that developed, with its complex intelligence apparatus, decisively reduced losses of merchant ships bound for Britain and safeguarded the massive American troop movements to France.

Allied convoy systems during World War II achieved worldwide dimensions, owing to the phenomenal range of Germany's commerce-raiding effort, which included a substantial Luftwaffe threat in the North Sea, the Arctic, and the Mediterranean. The Allies virtually eliminated Germany's surface raiders during 1943, but German U-boats, operating singly or in "wolf packs" of fifty or more submarines, extended "tonnage warfare" strategy from the North Atlantic to the Caribbean, the South Atlantic, and ultimately the Indian Ocean. Allied experience indicated both the suicidal impracticality of independent merchantman sailings and the striking economy of large convoy formations, particularly as land and carrier-based air cover, pinpoint location of individual stalkers by radar and high-frequency direction finders, and evasive convoy-routing procedures increasingly hampered U-boat reconnaissance patrolling.

With the advent of nuclear weaponry, the wide dispersion of convoyed shipping, and the employment of aerial transports, as during the Berlin Airlift (1948–1949), became characteristic elements of modern convoy operations.


Marcus, Geoffrey J. A Naval History of England: The Formative Centuries. London: Longmans, 1961.

Morison, Samuel Eliot. The History of United States Naval Operations in World War II. Boston: Little, Brown, 1947.

Roskill, Stephen W. The War at Sea: 1939–1945. London: H. M. Stationery Office, 1954.

United States, Department of the Army. Military Convoy Operations in the Continental United States. Washington, D.C.: Headquarters, Dept. of the Army, 1981.

Philip K.Lundeberg/c. w.

See alsoMerchantmen, Armed ; Shipping, Ocean ; Submarines ; World War I, Navy in ; World War II, Navy in .

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