Mirin had its birth more than 500 years ago as a thick, sweet drink. According to ancient Japanese texts, around the twelfth century, the Japanese began mixing cooked sweet glutinous rice with sake (rice wine) to enjoy as a festive drink. However, due to its high yeast and natural sugar content, this mirin-like beverage spoiled easily. In an effort to prolong shelf life, brewers in the warm southern islands began distilling this sweet rice-wine drink in the sixteenth century. The clear alcoholic concentrate that resulted, called shochu (literally, "fiery spirits") was about 80 proof and tasted somewhat like vodka. Shochu did not spoil in warm climates. Over the next few centuries, breweries in Japan's central region experimented by adding natural enzymes and sweet glutinous rice to the shochu. The mixture underwent long aging and purification, after which the thick, sweet liqueur was bottled, becoming one of Japan's most exclusive and expensive alcoholic beverages. (Although mirin's 14 percent alcohol content is similar to that of wine, it is more closely related to liqueur or brandy because it is distilled.) Later, as its seasoning virtues were discovered, mirin became a dominant flavor in the traditional art of kaiseki, Japan's highest form of cooking.
By the 1940s production of mirin was a thriving industry with over 200 producers, however, the processing of mirin did not survive the rice shortages of World War II or the post-war 76 percent liquor tax. As reported in the Asahi Shimbun, Japan's leading daily newspaper, by 1959, the Sumiya family business was the only company in Japan using the traditional methods of mirin brewing. Sumiya Bunjiro Shoten was sole keeper of the flame until recently, when a handful of companies began the production of authentic mirin.