History: Retro Swimsuit

In 1907 the swimmer Annette Kellerman from Australia visited the United States as an "underwater ballerina", a version of synchronized swimming involving diving into glass tanks. She was arrested for indecent exposure because her swimsuit showed arms, legs and the neck. Kellerman changed the suit to have long arms and legs and a collar, still keeping the close fit that revealed the shapes underneath. She later starred in several movies, including one about her life.
After this, bathing wear started to shrink, first uncovering the arms and then the legs up to mid-thigh. Collars receded from around the neck down to around the top of the bosom. The development of new fabrics allowed for new varieties of more comfortable and practical swim wear.
Due to the figure-hugging nature of these garments, glamour photography since the 1940s and 1950s has often featured people wearing swimsuits. This subset of glamour photography eventually evolved into swimsuit photography exemplified by the Sports Illustrated annual swimsuit issues.