S. Rosen’s Baking Company was founded in Chicago in 1909 by Sam Rosen, who left his home in Poland at age 9 to become an apprentice baker in Germany. Rosen came to the U.S. at age 13, opened his own bakery in New York at 16, and helped organize the first bakers’ union in that city. That activity cost him the hearing in one ear when a strikebreaker hit him over the head. ​

He moved to Chicago in his early 20s, purchased a small bakery on Chicago’s Northwest side called the New York Baking Company, and introduced Rosen’s now-famous rye bread to the Windy City. The bread used to be delivered unwrapped before dawn by horse and buggy, and placed in wooden breadboxes that were situated outside grocery stores.

S. Rosen’s has continues to be part of Chicago and the Rosen family. Don Rosen, the son of founder Sam Rosen, joined the company in 1945 and took the reins after his father retired. Steve Rosen, Don’s son, joined in 1974 and today serves as Vice President and General Manager. Sam’s great grandchildren also are continuing on the legacy and are in several key positions within the company.