Do you have the answer choices?
This depends on the time period but the only time that they spread their influence they didn't do it nicely so i would say the firearm ,"GUN" is the invention that helped them <span />
Answer:
George Stephenson
George Stephenson, (born June 9, 1781, Wylam, Northumberland, England—died August 12, 1848, Chesterfield, Derbyshire), English engineer and principal inventor of the railroad locomotive.
Explanation: