During the 1970s, rock climbing gained popularity in California, and climbers began prioritising functionality in their clothing. Rugby shirts - originally imported from England, New Zealand, and other countries - were quickly embraced by the climbing community. Commonly found in thrift shops, these shirts became highly sought after due to their thick, durable fabric, which made them ideal for the rigours of rough terrain. The growing demand eventually led many outdoor brands to develop their own versions, adapting the design specifically for climbing and outdoor use.