William Larimer Jr. was an American pioneer and businessman known for founding the city of Denver, Colorado, in 1858. He established a trading post near the confluence of the South Platte River and Cherry Creek, which attracted settlers and traders to the area. His vision for the settlement laid the groundwork for what would become a major urban center in the American West. Larimer's contributions extended beyond the founding of Denver; he also played a role in the development of the surrounding region. He was involved in various business ventures, including mining and real estate, which helped stimulate economic growth in Colorado during the mid-19th century.