The introduction of the convoy system in World War One was a desperate attempt to stem shipping losses due to the U-boat campaign. The tactic of the convoy - groupings of merchant ships escorted by a screen of warships, was not a new one. There had been convoys in times of conflict for centuries.   Even in peacetime, convoys were used to protect sea commerce from the ravages of piracy. Throughout history pirates have been the scourge of merchant shipping. From the Elizabethan era, state-sponsored piracy, in the form of the privateer, added to the menace.

The convoy system had seen it's greatest usage during the Napoleonic War and American War of Independence, when groups of up to a hundred ships would assemble in Cork Harbour for convoy to America and the West Indies. One one occasion the press reported one hundred and forty merchant ships moored in Cork Harbour awaiting convoy.

The convoy system was resisted during most of World War One. The British Admiralty largely saw it as an outmoded tactic, not suitable for modern warfare. They thought that concentrated groups of ships would provide an easy target for submarines and raiders. In fact the opposite was true, with lone ships providing the easy pickings of the u-boat campaign.

It was the United States Commander of Naval forces in Europe, Admiral W.Sims who was the greatest advocate of the convoy system. It was eventually adopted in the summer of 1917, and proved a great success, continuing until war's end. Convoys have continued to be used to this day, vindicating the system.

Queenstown was used as an assembly point and departure port for convoys leaving Europe, from August 1917 to January 1918. For the rest of the war. English and French ports were used, with Liverpool, Brest, Southmpton, Le Havre and Cherbourg becoming the most important by the Armistice.

It must be remembered that the vast majority of cargoes were transported to, not from Europe. It was the ports in the USA, Canada, South America,Australia,New Zealand and West Africa that were the source of food and materials that kept the Allied war machine in operation. Much of Europe, especially Britain, would have starved without these supplies.

Troop transports from North America took a slightly different route. Troop movements were mainly done in fast convoys, staying in deep water, direct from America to the French ports.

Queenstown was a vital port in the convoy system, with up to 37 United States destroyers, 12 Royal Navy sloops, and occasionally a few British destroyers based there.

There was also the important support of the Auxiliary fleet of trawlers, rescue tugs and motor boats. In 1918 there were also United States battleships based in Berehaven, British and American submarines, and a fleet of subchasers. In August 1918 there were also United States Flying boats in operation from Lough Foyle, Wexford, Whiddy Island, and Aghada in Cork.

The Queenstown destroyer and sloop force did not only escort the outward Queenstown Convoys, but would meet incoming convoys and single ships from all over the world. In great feats of seamanship, an incoming convoy, or single troop ship, would be met by Queenstown warships, hundreds of miles out in the Atlantic. Then they would be escorted to their final destination.

The navigational skills of these ocean rendezvous were astounding. There was no satellite navigation, bad weather meant that astral navigation was sporadic, and radio communication was rudimentary at best. There were some terrible accidents and mishaps, but the facts that these tasks were accomplished speaks volumes of the seamanship and bravery of these sailors, both merchant and naval.

The Queenstown convoys were given the designation 'OQ' followed by the number of the convoy, eg; OQ27 - Outward, Queenstown, convoy 27. Homeward convoys were given a 'H' designation and their originating port, eg: HH27 - Homeward Hampton Roads, convoy 27.

For security reasons, the port of destination was never given on these convoy designations.

In total there were 31 'OQ' convoys. Of these, Twenty five left from Queenstown, one left from Milford Haven in Wales, one left from Rosslare via Queenstown, One departed from Rosslare direct. Three were cancelled.