Its common to show the evils of modern society by a picture of the evolution of the female swimsuit, from a swimming-dress to a one piece to a bikini. This “evolution” is a complete lie.
In ancient times people swam naked. Romans, Greeks, Britons, etc all considered it normal for swimmers to be nude. Often it was even coed (women and men together) though some Roman emperors forbid the practice, which only shows how widespread it was. Some women in antiquity did wear two pieces outfits but only while doing exercise, not while swimming. (See attached picture).
So where did swimming suit “modesty” come from? It was only invented by the 17th-19th century Europeans.