Originally for Hygiene
Did women long ago wear anything under their skirts? Probably, not. Sometimes “leggings” were worn for warmth, and eventually drawers, loose fitting underpants or underwear for girls and women, were worn perhaps as early as the 1400s. These early undergarments or “unmentionables” had cords to tie them around the waist. They were invented in part to help keep outer clothing clean.
During the Regency Period (early 1800s) Pantaloons, which were often flesh colored, were made for modesty and warmth to be worn under the loose light-weight dresses.Pantaloons might be knee or ankle length.
In the late Victorian Era (1870-1900) women’s undergarments were again called drawers.
A one piece underwear also popular in the late 1800s was the Union Suit, a type of long john. They were first made for women and then became popular with men, too. They usually reached from neck to ankle and to wrist.
Bloomers invented by Elizabeth Smith Miller were popularized by Amelia Jenks Bloomer. These loose fitting undergarments were commonly worn by the Gibson girls (1890 to 1910) who wanted less restrictive clothing, for such activities as bicycling.
In the Roaring Twenties, the flapper styles called for shorter underwear named Step-ins. These white panties were loose at the legs. The elastic at the legs and colored panties came later.
Hip-huggers and bikini underwear made their appearance in the 1960s.
From Brazilian exotic dancers the G-string became popular in the 1980s, followed in the ‘90s by the thong.
Boy shorts popularity rose in ‘00s. These are often made of stretchy/clingy material and look like an abbreviated version of 1920s tap pants or men's briefs. Boy shorts cover the pelvic area and the upper part of the upper legs.
The basic panty has soft fabric, often with elastic at the waist, hips, or below, and covers crotch, front, rear and sides. Changes in fashion lowered the top, raised leg line, added decorations, see-through sections, or cut-outs, etc.
In some countries, such as Britain and Australia, panties are called knickers. Panties that completely cover from waist to top of leg are often called granny underwear.
What probably started out made from linen, undergarments are now made from cotton, silk, satin, tricot, nylon, stretch lace, etc.