Speedee appeared on McDonald's logo and branding before the Golden Arches became dominant.
The character was created to symbolize the McDonald brothers' Speedee Service System, which they introduced in 1948 after reorganizing their restaurant around fast, standardized production. Speedee was drawn as a smiling chef with a hamburger-like head, linking the figure to both food and rapid service.
Early McDonald's signs used Speedee as a recognizable emblem at a time when the company had not yet developed the globally familiar arches identity. As the chain expanded and the arches became more important, Speedee gradually disappeared from the principal branding.
This history explains why Speedee is sometimes described as McDonald's first logo mascot rather than simply an advertising character. Ronald McDonald was a later creation, first appearing in television commercials in 1963. The Hamburglar and other McDonaldland figures came later still, so none of them preceded Speedee in the company's branding history.