In 1923 after accidentally tanning on the French Riviera, French designer Coco Chanel started a trend of tanning, which began to be associated with health and leisure. The new trend fit in with shorter hemlines and rebellions against Victorian values. In 1928, designer Jean Patou created the first tanning oil, Huile de Chaldée. In 1935, Ambre Solaire, a tanning oil that absorbed UV rays, was developed by pharmacist Eugène Schueller, whose company later became L’Oreal. Coppertone introduced their sunblock in the 1940s, and bikinis arrived in 1946, showing even more skin to the sun.

Source: Bronze Tan