New York. Entenmann's is a company that manufactures baked goods and delivers them to supermarkets and other retailers for sale to the public. Entenmann's as a company is over 120 years old and originated in New York City. William Entenmann learned the trade of baking from his father in Stuttgart, Germany, and used his acquired skills to work in a bakery in the US, eventually opening his own bakery in 1898 in Brooklyn. Home delivery was a substantial part of the bakery that William owned, eventually turning into 30 home delivery routes by the time his son, William Jr, took over the bakery. While William Jr headed the bakery, it flourished; Frank Sinatra was a weekly customer. William Jr died in 1951, leaving the bakery to his wife Martha and their sons. The family decided to phase out bread, to focus on pastries and cakes, and to start supplying grocery stores as opposed to home delivery. In 1959, the Entenmann family invented the "see-through" cake box used by many today. The pharmaceutical company Warner-Lambert purchased Entenmann's in 1978, and then sold it to General Foods in 1982.