The oldest known shirt is Egyptian linen from about 3000 BC
A shirt covers the upper body from neck toward waist. Flinders Petrie found the oldest preserved garment—a finely pleated linen shirt—in a First Dynasty tomb at Tarkan, dated around 3000 BC. For most of history the men’s shirt was underwear; only in the twentieth century did it fully surface as outerwear.
In American English the word now covers almost any top, but in British usage a shirt specifically means a collared garment with cuffed sleeves and a full buttoned or snapped front, what Americans call a dress shirt. The Tarkan find is remarkable for its tailoring: pleats at the shoulders and sleeves gave a close fit with freedom of movement, and the woven fringe along one edge was placed to trim the neck and side seam. Although women wore the similar chemise, it was the male garment that evolved into today's shirt.
Medieval shirts were plain and undyed, worn against the skin, and artists showed them uncovered only on lowly figures such as shepherds, prisoners and penitents. By the 17th century men could let them show, with roughly the charge that visible underwear carries now. Sixteenth-century versions gained embroidery, lace and frills, and long neck ruffles called jabots stayed fashionable through the 18th century. Coloured shirts emerged in the early 1800s, as George Caleb Bingham's paintings show, but counted as workers' clothing: a sky-blue shirt was unthinkable for a gentleman in 1860 and standard by 1920.
Women adopted the shirt in 1860, when Empress Eugénie popularised the red Garibaldi shirt of the Italian freedom fighters. The idiom about giving the shirt off one's back is first documented in 1771. In 1827 Hannah Montague, an upstate New York housewife tired of laundering whole shirts for a dirty collar, cut her husband's collars off and invented the detachable collar; collar stays caught on only in the 1930s.
Variants multiplied: the four-pocket embroidered guayabera, the frilly poet shirt, the polo with its longer tennis tail, the raglan tee, and the light-brown thousand-miler that American travelling salesmen favoured because it hid road dirt. Legend supplied darker examples, like the poisoned Shirt of Nessus that killed Hercules.
Source: Shirt