In 1903, William S. Harley and Arthur Davidson built their first motorcycle inside a small wooden shed in Milwaukee, Wisconsin. Arthur’s brothers, William and Walter Davidson, helped with the effort. That first machine was straightforward — a single-cylinder engine fitted to a bicycle frame. It was basic, but it worked, and it started everything.
The company was officially incorporated in 1907. The Davidson brothers took charge of production while Harley focused on engineering. As demand grew, so did the facilities. By 1910, the company had moved into a purpose-built factory on Juneau Avenue in Milwaukee — the same address that serves as company headquarters today. The original shed was long gone, replaced by an expanding industrial operation that kept growing year after year.
A major technical leap came in 1909 with the introduction of the first V-twin engine. It produced more power than the single-cylinder models and had a deep, rumbling exhaust note that would define the brand’s sound for generations. The 1910s brought further improvements, including the “F-head” engine design and better frame and suspension systems, making the bikes more dependable on rough roads.
During World War I, Harley-Davidson supplied thousands of motorcycles to the U.S. military. The wartime contracts pushed production to new heights and proved the machines could hold up under demanding conditions. That reputation for durability stuck.
The 1920s marked the company’s peak early success. Harley-Davidson became the largest motorcycle manufacturer in the world, with dealers operating in 67 countries. New models featured larger, more powerful engines, and front-wheel brakes were added as a practical safety upgrade.
The Great Depression hit hard in the 1930s. Motorcycle sales dropped sharply, and the company had to find new ways to stay afloat. Harley-Davidson introduced three-wheeled utility vehicles and marketed their engines for industrial use. Even so, engineering work continued. In 1936, the company released the “Knucklehead” engine, an overhead-valve design that delivered more power and set the stage for future models.
Harley before they hired their color-blind marketing execs.