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Bermuda Gazette of 12 November, 1796, calling for privateering against Spain and its allies, and with advertisements for crew for two privateer vessels.

Commerce raiding or guerre de course is a naval strategy of attacking an opponent's commercial shipping rather than contending for command of the sea with its naval forces. The objective is to sink or destroy the logistics (supplies) of an enemy, rather than engage the combatant themselves.

Commerce raiding was heavily criticised by the naval theorist A.T. Mahan, who regarded it as a distraction from the destruction of the enemy's fighting power. Nevertheless, commerce raiding was an important part of naval strategy from the Early Modern period through until the Second World War.

Usually, commerce raiding is chosen by a weaker naval power against a stronger, or by a nation with little ocean-going trade against one with a great deal. The best protection against commerce raiding strategy is for merchant vessels to sail in convoy, protected by naval escorts.

The first sort of commerce-raiding was for nations to commission privateers - privately-owned ships authorised to attack and capture enemy merchants. Early instances of this type of warfare were by the British and Dutch against the Spanish treasure fleets of the 16th Century, and which resulted in financial gain for both Captain and crew upon capture of enemy vessels ("prizes").

This quickly became a major commercial enterprise, with privateer vessels, often in groups, being outfitted by venture capital, with investors also sharing in the returns. The practice rapidly spread. A privateer was distinguished from a pirate by the letter of marque, by which the vessel was commissioned as a private man-of-war. Captured vessels and cargo were submitted, in Britain's case, to Admiralty courts, where they might be condemned for sale, or, if the captures were not found to be within the rules of war, they might be released, sometimes with awards for damages.

During Britain's wars against revolutionary and Napoleonic France, the Royal Navy dominated the seas. France adopted a guerre de course strategy by licensing civilian privateers to seize British shipping.

During the American Civil War, the Confederacy operated a fleet of privateers and naval commerce raiders. The naval raiders include the CSS Sumter, CSS Florida, CSS Alabama, and CSS Shenandoah. Most of the ships used in this period were built in Britain.

By the 1880's, the navies of Europe began to deploy warships made of iron and steel. The natural process that followed, was more powerful guns to penetrate the new steel warships, which came with the inherent quality of more destructive power. No longer would navies fight for "prizes", in which capture of the enemy warship meant financial gain for Captain and crew, as well as their government when the prize and her cargo went under the hammer (only one warship was sunk at Trafalgar in 1805). The advent of steel and armor-piercing shells now meant the destruction and sinking of enemy "Men O' War"; first seen at Sinope in 1853, the change was little appreciated until 1905, when at Tsushima seven ships of the line were sent to the bottom, and the only "prizes" were those that had voluntarily surrendered upon the high seas, for the last time in naval history.

During World War I and II, the First and Second Battle of the Atlantic saw Germany conducting guerre de course against Britain and its allies, mainly using U-Boats. Germany could not build a large battle fleet as it had during WWI, and chose to concentrate on air and land power instead. U-Boats were cheaper and quicker to build than capital ships, and consequently Germany built up submarine rather than surface strength. This meant Germany would not be able to fight a war of "guerre d'escadre" (battles between fleets), but would have to pursue guerre de course; what small numbers of surface warships Germany possessed would also participate.

During World War II, the United States Navy used its submarine fleet to pursue a merchant war against Japanese shipping, while the US Navy's surface fleets conducted offensive fleet engagements against the Imperial Navy. The bulk of the Japanese merchant marine was sunk by American submarines. By the end of the war, Japan only had 12% of the tonnage of her pre-war shipping afloat.

The Indian Ocean raid was a naval sortie by the Carrier Striking Task Force of the Japanese Navy from 31 March to 10 April 1942 against Allied shipping and bases in the Indian Ocean. It was an early engagement of the Pacific campaign of World War II.

The staff of the Imperial Japanese Navy decided to send some raiders to Indian Ocean waters during December 12,1941-July 12, 1942. The Germans had already been operating in the area and conducted mutual aid with Japanese submarines, in the form of re-supply and military intelligence. The Indian Ocean was the largest operating area involving direct contact between the two axis partners, in which their primary objective was to keep the pressure on the shipping lanes. The Japanese Navy participated in Raider Warfare, but concentrated their powerful fleets on "Guerre D' Escadere", Fleet Warfare in the larger areas of the vast Pacific Ocean.

• Tonnage war
• Unrestricted submarine warfare
• Merchant raider
• German auxiliary cruiser Atlantis
• Indian Ocean raid
• Axis naval activity in Australian waters
• Japanese raiders in Indian Ocean Campaign
• Q-ship

• The Last Raider by Douglas Reeman (isbn 0-09-905580-5 Arrow books) Novel detailing the last voyage of a WW I German commerce raider.

• Brown, David. Warship Losses Of World War II. 1995. ISBN 155750914X
• Blair, Clay, Jr. Silent Victory. Philadelphia: Lipincott, 1975.
• Mahan, Alfred, Captain. Influence of Seapower on History.