A doublet (derived from the Ital. giubbetta) is a man's snug-fitting jacket that is shaped and fitted to the man's body which was worn in Spain and was spread to Western Europe from the late Middle Ages up to the mid-17th century. The doublet was hip length or waist length and worn over the shirt or drawers. Until the end of the 15th century, the doublet was usually worn under another layer of clothing such as a gown, mantle, overtunic or jerkin when in public.
Originally it was a mere stitched and quilted lining ("doubling"), worn under a hauberk or cuirass to prevent bruising and chafing. Doublets were sometimes opened to the waistline in a deep V. The edges might be left free or laced across the shirt front. If there was space left it might be filled with a stomacher. By the 1520s, the edges of the doublet more frequently met at the center front. Then, like many other originally practical items in the history of men's wear, from the late 15th century onward it became elaborated enough to be seen on its own.
Throughout the 300 years of its use, the doublet served the same purpose: to give fashionable shape and padding to the body, to support the hose by providing ties, and to provide warmth to the body. The only things that changed about the doublet over its history was its style and cut. It was fashionable until the 1600s.
From the late 14th century, doublets were cut and padded to give the wearer an egg-shaped or pigeon-breasted silhouette, a fashion that gradually died out in favor of a flatter natural fit.
Through the Tudor period, fashionable doublets remained close-fitting with baggy sleeves, and elaborate surface decoration such as pinks (patterns of small cuts in the fabric), slashes, embroidery, and applied braid.
In the early Elizabethan period, doublets were padded over the belly with bombast in a "pouter pigeon" or "peascod" silhouette. Sleeve attachments at the shoulder were disguised by decorative wings, tabs, or piccadills, and short skirt-like peplums or piccadills covered the waist of the hose or breeches. Padding gradually fell out of fashion again, and the doublet became close-fitting with a deep V-waistline.
By the 17th century, doublets were short-waisted. A typical sleeve of this period was full and slashed to show the shirt beneath; a later style was full and paned or slashed to just below the elbow and snug below. Decorative ribbon points were pulled through eyelets on the breeches and the waist of the doublet to keep the breeches in place, and were tied in elaborate bows.
The doublet fell permanently out of fashion in the mid-17th century when Louis XIV of France and Charles II of England established a court costume for men consisting of a long coat, a waistcoat, a cravat, a wig, and breeches—the ancestor of the modern suit.