As long as there have been spirits to drink, there have been people adding more flavor to those spirits and dosing the concoction with sugar to make it more palatable.
Traditional liqueurs exist all over the world—bitter red Italian liqueurs, Scotch whisky liqueurs, German licorice-infused liqueurs, limoncello, sambuca, triple sec, sloe gin, and more. Many of these styles have their own unique histories that span centuries. Going back even to ancient times, there is some evidence of crude distillation for purposes that likely included perfumes and medicinal tinctures based on various botanicals. Over time and through study, people found that alcohol was a better solvent than water—alcohol could extract more flavor and was a better preservative.
To understand the wide world of liqueurs, it helps to first understand how they’re made. As flavored spirit-based drinks, most liqueurs fall between 15 and 30 percent ABV and have a sugar content of at least 10 percent. While almost all commercial examples are within those specs, many stylistic, economic, and regional choices lead to a wide landscape of distinct products.