The History of Square Rig Sailing
This two-masted full-rig ship has all her canvas set.
Square rig sailing is believe to have originated with the Vikings of the 9th and 10th centuries, using square sails on their longships more than 1200 years ago. Square rig sailing was the most common sail rig configuration in use for commercial sailing ships, naval warfare, and exploration, up until steam power began taking over.
The single-mast configuration of the Viking ships lasted until the 15th century, when the two-masted ship was introduced. The second mast was usually located aft of the main mast and frequently carried a 3-cornered sail. The mast was the mizzen mast, and its sail was the mizzen sail.
The introduction of galleons — smaller, better armed, and more maneuverable — brought with it the use of a third mast, this one located forward of the main mast and called the fore mast.
Naval Warfare Spurs Development of Staysails
When naval warfare grew during the 17th century, warships began carring more sails of all types. The staysail was developed during this time. The staysail is a fore-and-aft rigged sail. Staysails are most commonly attached to the forestay of the forward mast, the supporting line that runs diagonally from the top of the foremast or mainmast to the bowsprit, but staysail refers to any sail rigged to a mast's stay.
Sail Rigging is Further Refined
During the 19th century, the Napoleonic wars brought further refinement of square rig sailing configurations, and the clipper was designed after the British Navy handily beat the Americans in the war of 1812. The clipper was developed for speed, often capable of reaching 20 knots, in contrast to the 5-6 knots attained by other cargo ships of the day.