Could the Romans Have Built a Steam Engine?

Most obviously, the Romans could have built a steam-powered railroad, as even railroads, surprisingly, were also in common use at the time. Putting a heavy steam boiler on tracks and getting it to turn wheels fitted to a low-friction track is an obvious application, once you've got a good engine.

Did Romans invent a steam engine?

So, the short answer: Could the Romans, Byzantines, or Chinese have built a steam engine? No. They lacked the necessary machine tools, and the knowledge of centrifugal governors.

Did the Romans discover steam power?

There is the actual first recorded steam engine in history, Hero of Alexandria's Aeolipile. Widely published and noted in the Roman world, this device demonstrated that steam could be used to convert heat into work. There is little evidence of it actually being used for practical purposes, however.