At Home Mechanic

We know why the Japanese drive on the left side of the road, the first cars built in Japan during the 1920's were reverse engineered British cars. Why did the Japanese copy the British cars rather than French, German or American cars? Because as the Japanese emerged from their self imposed world isolation in the mid-19th century, they chose to follow the industrial and military example of the British who were arguably the most important and influential economic and military of the period. The Japanese navy that soundly defeated the Tsar's navy of Imperial Russia in 1906 was nearly entirely composed of British build warships and the officer corps was trained by the British Navy.

The Swedes used to drive on the left hand side of the road and decided to switch in the mid-1960's. But the Swedes realized that their best export market for their cars was the rest of Europe and the United States and that it was in their best interest to drive on the right side of the road.

The Brits like to explain their choice of driving on the left side of the road dates back to ancient times when a knight on horse back would keep his weapon hand (the right) toward approaching travelers so that he could defend himself in an instant. And this sounds convincing on the surface. But if you have ever traveled on the old roads of the English countryside that have not been widened or otherwise modernized you know that they are terribly narrow. Back in the day of knights and the such, everyone rode down the middle of those narrow lanes and moved to one side or another as the situation permitted.

It was not until the English Industrial Revolution of the 18th Century and the rise of commerce that traffic patterns became a problem. Horse-drawn wagons were soon crowding the roads as good were being brought to market. It became apparent that a system was necessary to insure the orderly flow of traffic. But what side of the road should all traffic stick to?

Imagine a horse drawn wagon. The driver sits up front with the reigns in his hands with which he steers the wagon. And the only means to slow or stop the wagon was a long lever by the driver's leg that could exert some muscle-powered friction on one of the wagon wheels. Aha! What leg is strongest for most people? Their right. So for the driver of a wagon to use his strong right leg to slow his wagon, he would have to sit on the right side of the wagon's front seat.

And if two wagon drivers met on a narrow road and they wanted to insure that there was no collision, they would each have to travel on the left side of the road as they traveled so that their seated position could afford the best view of the passage.

So while it is romantic and exciting to think of dashing knights on the road challenging each other to a duel on the narrow roads of the English countryside, it is really the rather mundane world of 18th century business and commerce that dictated the rules of the road that the British have kept to this day.