The earliest clear link between an industrial-age innovation and the first locomotive is the steam engine, adapted for use on rails. In the Industrial Revolution, the steam engine evolved from early pumping engines to high- pressure engines, and engineers harnessed that power to drive locomotives. The first practical steam railway locomotive is generally credited to Richard Trevithick in 1804, whose high-pressure steam locomotive demonstration and subsequent engines laid the groundwork for rail traction. By the 1820s and 1830s, steam locomotives designed for passenger service—most famously George Stephenson’s Rocket—demonstrated reliable, powered rail travel on public lines, marking the locomotion of the era. Key points:

• The core antecedent innovation is the steam engine, refined to operate under higher pressures and to deliver rotary motion suitable for driving wheels. This transition from stationary power to mobile rail propulsion was the decisive step in creating the first locomotive on a functional railway system.
• Trevithick’s 1804 locomotives are widely regarded as the first successful demonstrations of a locomotive-powered rail vehicle, showing the feasibility of using steam power on iron rails.
• The subsequent design and testing work by Stephenson, leading to the Liverpool–Manchester line and the Rocket’s performance in 1829, solidified the steam locomotive as the defining technology of early rail transport during the Industrial Revolution.