The first speed limits were set in the United Kingdom in a series of Locomotive Acts in 1861, 1865, and 1878.  The 1861 Act set the speed limit at 10 mph (16 km/h).  In 1865, the “Red Flag” Act reduced the speed limit to 4 mph (6 km/h) in the country and 2 mph (3 km/h) in towns and required a man with a red flag or lantern to walk 60 yards ahead of the vehicle to warn people of the upcoming self-propelled machine.  The 1878 Act removed the need for the red flag and reduced the distance of the escort to a reckless 20 yards.   Yes, it was a pretty crazy time.  Vin Diesel starring in “The Fast and The Furious: Self-Propelled Machines”