Charles Rudolph Walgreen

Walgreen was a registered pharmacist who had worked behind other people's counters in Chicago before buying the drugstore he worked in, in 1901, with a loan from his father. From the dispensary he knew which products customers came back for, so he made his own medicines more cheaply and added a soda fountain that kept people in the shop; the malted milkshake became a draw. Scaling to hundreds of stores meant learning finance and real estate, which his managers helped carry.