The radicalization of women's swimwear throughout the 20th century was closely intertwined with the evolution in gender politics. The transformation of women’s swimwear from concealing to revealing --from 19th century “bathing gowns” that were long flannel dresses to provocative bikinis today-- must be analyzed in comparison to men’s swimwear of their respective historical contexts to understand the dichotomous double standards they reflected perpetuated.

The 1920s marked the liberalization of both men’s and women’s swimwear, albeit according to stark double standards. As it became socially acceptable for men to bathe topless, meanwhile, for the sake of including women in sports, women’s bathing suits shrank to more practical wool-knit one-pieces. Tighter-fitting swimwear that allowed for greater movement was a tremendous milestone in women’s fashion, as, for the first time, function and comfort were prioritized over the societal expectation of concealing their bodies. Additionally, the rise of beauty pageants in the 1920s also popularized less conservative swimwear. In the first Miss America pageant in 1921 in Atlantic City, female adolescents gathered on the boardwalk in tight, wool one-piece swimsuits, and were judged by a panel of male judges; as this event infiltrated the media, similar swimwear became increasingly pervasive on the womenswear market.

On July 5, 1946, French engineer Louis Reard revealed the first modern bikini at the Piscine Molitor swimming pool in Paris. He had constructed the garment out of less than 30 inches of fabric and called it the “world’s smallest bathing suit.” French showgirl and model Micheline Bernardini modeled the garment. Named after the Bikini Atoll, a site for post-war atomic bomb testing, the bikini became an instant hit. It immediately received 50,000 fan letters, mostly from men. Reard’s invention was a continuation of a twentieth century movement that sought to create more practical swimwear for women and to conserve fabric for military purposes. Although women accepted the bikini in France and Australia, the bikini did not enter mainstream America until the 1960s, as it was perceived as naughty and “unladylike.” This was largely reflective of the conservative post-war ideology imbued in American culture at the time: women had gained empowering new roles as workers, volunteers, and single parents as their husbands fought in the war. After the war, however, Americans wanted to recreate traditional families. Although the number of working women grew during the 1950s, Americans pressured them to conform to traditional gender roles. Many people criticized women who dressed in exposing clothing, believing they should wear “feminine” attire as stay-at-home moms. This image of conformity became apparent in the representation of women in magazines, billboards and television shows.