“The generally accepted rule is pink for the boys, and blue for the girls. The reason is that pink, being a more decided and stronger color, is more suitable for the boy, while blue, which is more delicate and dainty, is prettier for the girl.”
-Earnshaw’s Infants Department, June 1918 ( X )
Sky blue and pale blue has traditionally been a colour for small girls and unmarried women in the Western world*. Blue was a calming, delicate colour suited to cool the temperament of girls. Red and pink, on the other hand, were energetic colours, suitable for boys, or for adult women.
In the early 20th century this was still the general rule, though softer pastels of both colours became popular for babies in general. The modern idea of pink for girls and blue for boys had a brief popularity from the 1940s and until the 1970s, then gender neutral clothes for children became fashionable. It lasted until the mid 1980s, where gender specific clothes again became the rage.
In other words, our current fancy of pink for girls and blue for boys stems from 1980s. It’s not how your grandparents or the generations before them were dressed as children. It’s a very new and Western idea.
The original iconography of sky blue being a girl’s colour can still be seen and understood through characters like Belle in “Beauty and the Beast”, Dorothy in “Wizard of Oz”, Alice in “Alice in Wonderland”, Disney’s Cinderella and Christine in ALW’s “Phantom of the Opera”.
*It’s not entirely Western, sky blue for female attires can be found in everything from Afghan burkas to Russian folk costumes. But my photos is from a Western perspective.