Why do people drive on the left in some countries and on the right in others?

The reason why some countries drive on the right and others on the left is primarily historical, cultural, and political, with roots that sometimes date back to the Middle Ages. Here are some general guidelines for understanding this difference:

Historical Origins of Driving on the Left

In the Middle Ages, most people (especially right-handed people) carried their swords on their left side and rode on their left side so they could easily draw their swords with their right hand.

Thus, it was more logical to ride on the left when crossing paths with another rider, while being able to defend or salute with their right hand.

Napoleon Bonaparte, being left-handed, is said to have imposed driving on the right in the territories he conquered, which influenced much of continental Europe.

The Napoleonic light cavalry

Colonial Influence

The British Empire retained driving on the left and imposed it on its colonies (India, Australia, South Africa, etc.).

Countries colonized by France or under Napoleonic influence adopted driving on the right (like most of Europe, French-speaking Africa, etc.).

Around 1930, people always drove on the left in Vienna (Austria)

Influence in America

In the United States, a law was passed in 1792 mandating right-hand driving, but some states took longer to comply. In Canada, some provinces historically drove on the left, but they all switched to right-hand driving over time, the last being Newfoundland in 1947.

Poster announcing the change of traffic from left to right in New Brunswick (Canada) in 1922.

French influence and the needs of wagon drivers also played a role in the adoption of right-hand drive.

In the 18th century, in the United States, a new type of cart, the Conestoga, would lead to right-hand driving in the country.

The Case of Japan

In Japan, people drive on the left. The steering wheel is therefore located on the right side of the vehicle. This practice, although different from driving on the right in France, is a historical adaptation dating back to the time when samurai carried their swords on their left side, making it easier to wield them with their right hand.

Driving on the left in Japan

Changes over time

In the 20th century, a few latecomers decided to switch sides. At 5 a.m. on September 3, 1967, it was "Dagen H," the day Sweden switched from driving on the left to driving on the right to align with its neighboring countries. The government held a referendum asking its citizens to express their views on the matter in 1955. And although a large majority voted against the transition to the right, it was adopted a few years later.

Dagen H (H-Day) is the day, September 3, 1967, when traffic in Sweden switched from driving on the left to driving on the right. The "H" stands for "Högertrafik," the Swedish word for "good traffic."

The reverse direction of the blue arrow road sign has become an iconic symbol of the Dagen H project

Other countries like China (1946), Burma did the opposite (moved to the right) in 1970, for internal political reasons. Nigeria (1972) and Samoa (2009) which are the last countries in the world to change the direction of traffic to drive on the left. They can thus buy cheaper cars in Japan, Australia or New Zealand.

Little by little, the countries that maintain a road network where vehicles drive on the left are losing ground. But there are still many of them, and the global road network will be standardized a long way off.

It's true, it would probably be simpler if that were the case. But behind all this confusion lies a multitude of stories and a touch of mystery.

After all, our world is riddled with anomalies. The road network is just another example.

Current Distribution

76 countries, or approximately 35% of the world's countries, drive on the left, including Japan, India, the United Kingdom, and Australia.

The other 65% drive on the right, or about 127 countries, such as France, Algeria, the United States, Canada, and Germany.

Conclusion:

Although right-hand traffic existed before, Napoleon contributed to its widespread adoption by imposing this direction of travel on his armies and conquered territories, partly for military reasons and to distinguish himself from Great Britain, which maintained left-hand driving.

A great strategist, Napoleon Bonaparte knew that, on the battlefield, fighting began on the left flank of the cavalry. To gain the advantage by exploiting the element of surprise, the emperor ordered his soldiers to fight with their left hands, which forced them to attack from the right.

The result paid off. Napoleon then decided to impose right-hand traffic on the roads for everyone. Everyone, except... the undefeated English.

When the automobile was invented, the right-hand traffic was retained to facilitate the coexistence of cavalrymen and motorists.

So nowadays, left or right, the main thing is to drive whatever the reason.