Jerry Thomas was a prominent American bartender in the 19th century, often referred to as the "father of American mixology." He is best known for his influential cocktail book, "The Bartender's Guide," published in 1862. This book introduced many classic cocktails and established standards for bartending practices. Thomas worked at various bars in cities like San Francisco and New York City, where he gained fame for his innovative drink recipes and flamboyant style. His contributions to the cocktail culture laid the groundwork for modern bartending and inspired generations of mixologists.