Uniform ('one shape') is the distinguishing dress of any special body of individuals—whether soldiers, sailors, or members of a society or club. Military uniforms in Great Britain may be said to date from the Restoration, and the consequent formation of a standing army. As early as Henry VIII.'s time the sovereign's bodyguard (now the Honourable Corps of Gentlemen-at-Arms in England and the Royal Archers in Scotland) received a distinctive dress. But this dress was several times changed—e.g. cloth of gold and silver became red and yellow damask in 1529, and then white and black shortly afterwards. The life guards and horse guards, formed in 1661 from the troops which had fought on opposite sides during the Great Rebellion, in buff coats, cuirasses, and steel caps, were then dressed in scarlet coats, feathered hats, and jack boots. Cocked hats were soon after given them, and in 1812 helmets. Somewhat similar changes have taken place in the rest of the army. Military uniform consists of a coat of one prevailing colour, variously ornamented and 'faced' according to rank and corps, a special head-dress and trousers or kilt. Scarlet may be said to be the national uniform of the British army, blue of the German and French. But this only applies to the tunic or jacket, and there are many exceptions. Thus British artillery and many cavalry regiments wear blue, all rifle regiments green, some regiments of the Indian army yellow, drab, and French gray, some colonial and other volunteers gray. In hot climates, during summer, only white uniform is worn, and the white helmet is universal for European troops. The kilted dress of the Highlanders is peculiar to the British army, but the black soldiers of the less well-known West India Regiment are dressed like Zouaves, the jacket being red and trousers blue instead of the reverse. Blue is the uniform of the United States army, the overcoat and trousers sky-blue, the blouse and uniform-coat dark-blue. The head-dress is a very distinctive part of the uniform. At home the Scots Greys and foot-guards wear bearskins, and all fusiliers hats of similar shape; hussars and horse artillery wear Busbies (q.v.), kilted regiments the feather bonnet, Highland Light Infantry the shako, rifle regiments now a small astrakhan busby, staff-officers cocked hats. All others wear helmets, metal for cavalry, blue cloth for other arms; native Indian regiments generally turbans. Forage caps of various patterns are worn in undress. Facings, formerly very prominent, are now confined to collars, cuffs, the busby bags of hussar regiments, and the breast-pieces of lancers' tunics. The rule is blue for royal regiments wearing scarlet, and vice versa; white for English, yellow for Scotch, and green for Irish, if not royal. Cavalry regiments do not follow this latter rule. The colours of the plumes too are very numerous—black, white, red, and a mixture of two of these colours, yellow or green. Generally all hussars and lancers wear blue, all other cavalry red tunics with blue overalls; but the 11th Hussars have crimson overalls, the 6th Dragoon Guards blue tunics, and the 16th Lancers red. Officers of all arms wear, in addition to other marks, badges of rank on their shoulder-strap. One star denotes a lieutenant, two a captain, a crown a major, a star and crown a lieutenant-colonel, a second star a colonel. Cross-swords added to these signify the various grades of general officer, and cross-batons a field-marshal. In the United States army the shoulder-strap of a second-lieutenant are plain, those of a first-lieutenant bear a silver bar at each end, those of a captain two silver bars at each end, those of a major a gold oak-leaf at each end (silver for a lieutenant-colonel); a colonel's shoulder-strap bear a silver eagle, a brigadier's a silver star, a major-general's two and a lieutenant-general's three silver stars, and the general's two silver stars with a gold eagle and device between. The Confederate uniform was gray.
Uniforms in the British navy were not laid down until the reign of George III. Like other nations, the prevailing colour is blue. Tail coats and epaulettes, discarded by the army after the Crimean war, are still worn by officers in full dress, and cocked hats. Rings of gold lace and badges on the epaulettes denote the rank (see EPAULETTE). In the United States navy dark navy-blue is the uniform colour, but in warm weather a service coat of white linen duck trimmed with white braid is substituted, and a white cork helmet may take the place of the cocked hat or service cap. All commissioned officers wear gold billon epaulettes on each shoulder; rank is indicated by strips of gold-embroidered white oak-leaves or of gold lace, and by devices on the shoulder-strap.
Since the beginning of the 19th century, with its development of field-sports and travelling, it has become usual for British officers not to wear their uniforms when off duty, save on special occasions. In 1815 officers sitting in parliament wore their uniforms; and twenty or thirty years later officers when on leave wore a frock coat—a spurious kind of undress of their own invention. The privilege of wearing plain clothes, now granted also to warrant officers, to a great extent rests with the general in command, and might at any time be withdrawn. In late wars, especially in South Africa, all British troops have worn practically the same uniform of khaki or dust colour.