Here is an interesting chart showing the timeline of current and defunct American car companies. Did you ever hear of an Ajax? Abbott? Moon? Staver? Hupmobile? A Timeline of American Automotive Brands: Current and Defunct - Your Automotive Information Resource - PartsGeek
This one was omitted. It was built in my hometown 113 years ago. Check Wikipedia The Multiplex was an automobile built in Berwick, Pennsylvania by the Multiplex Manufacturing Company (today: Crispin Multiplex Manufacturing Company; Crispin Valve) from 1912 to 1913.
They left out Marmon Trucks (1963-1997). The Department of Energy used modified versions to move product across the US.