It was built by the Oakland Motor Co., founded in 1907, in a buggy shop on Oakland Ave. in the city of Pontiac, Oakland County, Michigan. In 1926 Oakland's general manager, Alfred R. Glancy was credited with the name when upon taking over Oakland said, "When I got to the plant I found designs for it hanging on the wall and over them someone had written 'Pontiac'".
Yet when he got ready to christen the first Pontiac in 1926 with a bottle of champagne, he claimed the car was named after Chief Pontiac, who led the Ottawas, Chippewas, Pottawatomis and Miamis in a powerful indian federation in the mid-eighteenth century.
So, take your pick. Was it after the city of Pontiac, or the name Glancy found on the wall, or the Indian Chief Pontiac?