As The Telegraph reports, this particular facet predates automobiles and goes as far back as the Middle Ages. Back in those days, traveling on a highway put one at risk of getting mugged, so moving on the left side of the road was a matter of safety. As most of the people are right handed, it made sense to keep your right hand free to be able to whip out your sword, lance, pitchfork, etc. and respond to a threat while moving on the left.
And since Britain wasn’t the only one with dangerous roads, the practice of traveling on the left side can be seen in the ancient Greece and Rome traditions. It was notably Napoleon who was the first the propose a change as he made everyone in his colonies switch to the right side. Same was the case with Hitler in Germany, who forced Czechoslovakia and Austria to switch to right-side driving.
In contrast, America is probably one of the few British colonies where driving is on the right side of the road, probably out of abhorrence for of British customs. But another reason was that the practice made it easier to maneuver a wagon as the drivers sat on the left side of the wagon or led the horses on foot on the left-hand side. This also made it easier to watch the oncoming traffic and any other obstacles on the road.
Pennsylvania was the first state to regulate right-side traffic in 1792, followed by New York in 1804. Other states followed suit, but it was Henry Ford’s choice to put the widely popular Model T’s steering column on the left that cemented the practice until this day.
Watch the video below to learn more about the history of Right vs. Left hand drive: