March 9 in History

In March 1776, the Scottish philosopher Adam Smith published An Inquiry into the Nature and Causes of the Wealth of Nations, a long book that helped establish economics as a distinct field of study. Its central argument was that a nation's prosperity comes from the productive capacity of its people and the efficiency of its markets, not from stockpiles of gold and silver. The book became one of the most cited works in the history of economic thought, though its reputation as a simple manifesto for free-market capitalism is more a later invention than an accurate summary.

Barbie, the fashion doll that would become one of the best-selling and most debated toys in history, made her public debut at the American International Toy Fair in New York in March 1959. Produced by the Mattel toy company of California, she offered children something unusual for the time: a doll modeled on a grown woman rather than a baby. Her arrival reshaped the toy industry and began a decades-long conversation about gender, body image, and aspiration.