The Thomas B. Jeffery Company was an American automobile manufacturer in Kenosha, Wisconsin from 1902 until 1916. The company manufactured the Rambler and Jeffery brand motorcars. It was preceded by the Gormully & Jeffery Manufacturing Company, a bicycle manufacturer. It was the parent company to Nash Motors, thus one of the parent companies of American Motors and Chrysler.
Thomas B. Jeffery was an inventor and an industrialist. He was one of America's first entrepreneurs interested in automobiles in the late 19th century. In 1897, he built his first prototype motorcar. Thomas B. Jeffery was serious enough about automobiles to sell his stake in Gormully & Jeffery to the American Bicycle Company to finance the new car company.
Charles T. Jeffery's (Thomas' son) experimental prototypes of 1901 (Models A & B) used at least two radical innovations – steering wheels and front-mounted engines. By the time Charles was ready for production in 1902, his father had talked him out of these wild dreams and convinced him to stick with tillers and engines under the seat.
From 1902 until 1908, Jeffery moved steadily to bigger, more reliable models starting with the 1902 Model C. Jeffery cars were built on assembly lines (the second manufacturer to adopt them -- Ransom E. Olds was first), and in 1903 Jeffery sold 1,350 Ramblers. By 1905, Jeffery more than doubled this number. One reason may have been because Charles went back to the steering wheel before 1904. In 1907, Jeffery was building a large variety of different body styles and sizes. Among them was a five-passenger, US$2,500 Rambler weighing 2,600 pounds (1179 kg) and powered by a 40-horsepower (30 kW) engine.
In April, 1910, Thomas B. Jeffery, died in Pompeii, Italy and in June of that year the business was incorporated under the name of the Thomas B. Jeffery Company, with Charles T. Jeffery as the president and general manager, H. W. Jeffery, vice president and treasurer.