Henleys were first seen in nineteenth-century England, where they were used as men’s undergarments. These undervests, as they were called, were some of the first collarless underwear and were known for being easier to wear and more comfortable, but they soon took hold to a much greater degree as sportswear in the western English town of Henley-on-Thames.
Since 1839, the town of Henley had been the home of the Royal Regatta, the largest rowing race in all of England. Rowers enjoyed the increased ventilation from the placket and lack of collar and it soon became the standard rowing uniform. The crew racing tradition also contributed to the spread of the shirt, as the losers would typically give their shirts to the winners at the end of a race.
The henley shirt was also coming to popularity at the dawn of the Britain’s Industrial Revolution, and inventions like the cotton gin and water powered milling allowed for mass production on a scale that had never been seen before.