Birkenstocks, often called Birks, are a staple for young Americans today. The history of birks goes back to Johann Adam Birkenstock, a German shoemaker of the late 18th century Germany. His descendants would come to perfect the cork-based insoles that would adjust to the wearer’s foot shape. The orthopedic support the soles provided made Birkenstock sandals popular among returning soldiers post WWII. The sandals were introduced to the U.S. and non-German markets in the 1960s, although they did not become popular until the late 1970’s in the U.S., riding on a wave of hippie liberalism. In the 1990s, Birks became again popular with the Generation Xers, and have maintained mainstream popularity since.