McDonald's first mascot before Ronald McDonald was Speedee.
Speedee represented the restaurant's original promise of rapid service. The McDonald brothers introduced their Speedee Service System in 1948 after reorganizing their San Bernardino restaurant around a smaller menu, standardized portions, and efficient kitchen production. The mascot visually connected the brand to that operating concept.
This early identity differed from the later family-entertainment branding built around Ronald McDonald and McDonaldland. Speedee was primarily a symbol of service speed and restaurant efficiency, while Ronald was a character designed for television, children, and family-oriented marketing.
The answer is sometimes confused with “Speedee Service System,” which was the name of the operating method rather than the mascot itself. It is also distinct from Mac Tonight, a much later advertising character associated with a 1980s campaign. Speedee belongs to McDonald's earliest branding period.