In the waning months before the turn of the 20th century, A.R. Welch created the Chelsea Manufacturing Company with his younger brother Fred. They produced small metal novelties. By 1901 they had manufactured an automobile of their own design. It was a two-cylinder 20-hp engine with overhead vales and hemispherical combustion chambers, a highly advanced design for the time.

The car was shown at the Chicago Automobile Show of 1903, and production began soon after. The Welch brothers produced approximately 15 cars a month. However, in early 1904, financial problems caused them to file for bankruptcy.

Later that year A.R. Welch reorganized in Pontiac Michigan. Now, with stronger financial backing, he was able to develop a sturdier automobile. The original 20 hp Welch Tourist, with its relatively small 78-inch wheelbase, was transformed into a 78 hp, four and (later) six cylinder car with a 139-inch wheelbase. This was one of the largest, best-built and most luxurious automobiles of the time, and sold for a hefty $4,000.

In June of 1909 a separate company was set up in Detroit to produce a smaller, less-expensive car, which was named the Welch Detroit. During that year Welch became affiliated with General Motors, and the following year GM bought Welch out. The last Welch car was produced in 1911.

Welch announced in the fall of 1913 that he was nearly finished with his next project. This was a cyclecar with a 110-inch wheelbase, and as Welch described it, "a body as roomy as a touring car." However, this was not to be. On November 8, of that year Welch went duck hunting. There was a terrible storm and, although his canoe was found, his body never was.