Why Japan Drives on the Left

Japan drives on the left primarily because British engineers set a left-running standard on the nation’s first railways in 1872, a convention that spread to trams and road traffic and was later codified nationwide (notably in a 1924 central government order and retained under the postwar Road Traffic Law). A postwar exception in U.S.-administered Okinawa briefly flipped traffic to the right until the island reverted to the left in 1978. Folklore about samurai-era customs exists, but documentary evidence points to rail and legal standardization as the decisive causes.

Historical Roots: From Railways to Roads

While stories about Edo-period pedestrians “keeping left” to avoid clashing samurai swords are culturally familiar, the best-documented driver of Japan’s left-side road rule is the left-running standard established by its British-built railways in the late 19th century. That practice shaped infrastructure, signaling, and urban movement patterns that later informed road rules as wheeled traffic expanded.

Railways Set the Template (1872 onward)

Japan’s first railway, the Tokyo–Yokohama line opened in 1872, was engineered with extensive British expertise and operated on the left—consistent with British rail practice. As rail expanded nationwide, left-side running became the norm across the rail network. Urban tramways, which interfaced closely with streets and pedestrians, followed suit; this embedded a left-sided logic into stations, platforms, crossings, and city traffic flows long before automobiles were common.

Early Municipal Rules and Practice

As horse-drawn traffic and early motor vehicles appeared, major cities issued bylaw-style rules to manage congestion and reduce collisions. In Tokyo, police ordinances in the late 19th century required vehicles to keep left; other municipalities adopted similar measures. Though local in scope at first, the pattern was consistent: left-side traffic matched the prevailing rail and tram conventions and simplified urban traffic management.

National Standardization in the 20th Century

By the early 20th century, left-hand traffic was common in practice, but national rules solidified it. In 1924, a Home Ministry traffic order formalized left-hand road travel across Japan, harmonizing disparate local regulations. After World War II, the modern Road Traffic Law (1949) reorganized traffic governance but retained left-hand driving. From then on, the rule has been uniform nationwide—except for the temporary Okinawa anomaly after the war.

The Okinawa Exception: Switch and Switch-back

Under U.S. administration after 1945, Okinawa adopted right-hand traffic to align with American practice, while the rest of Japan remained left-hand. The divergence ended on July 30, 1978—“730 Day”—when Okinawa reverted to left-hand traffic to match the mainland. The changeover was a major logistical operation: roads were restriped, signs replaced or rotated, intersections reprogrammed, bus fleets adapted, and public awareness campaigns mounted to ensure a safe transition.

Myths and Realities

Several explanations circulate about why Japan drives on the left. Some are rooted in culture, others in comparative history. The points below distinguish commonly repeated claims from the historical record.

• Samurai-era etiquette: It’s often said Edo-period pedestrians kept left to avoid sword collisions. While plausible as local custom in crowded quarters, evidence is fragmentary and not sufficient to explain the nationwide modern rule.
• British influence: Well documented. British engineers helped build Japan’s first railways; left-running rail and tram systems strongly influenced road practice and later codification.
• “Imported car steering decided it”: Early automobiles in Japan came with both left- and right-hand drive configurations, but steering-wheel placement follows the side of the road, not the other way around; policy and infrastructure drove the choice.
• Empire alignments: Unlike many left-driving countries linked directly to the British Empire, Japan’s left-hand rule arose through technology transfer and regulation rather than colonial governance.
• Pan-Asian precedent: There wasn’t a uniform East Asian road rule before modern traffic laws. Notably, Korea and Taiwan drove left under Japanese rule but switched to the right after 1945 under new administrations.

Taken together, the record shows cultural practices may have primed people for left-side movement, but rail engineering and formal legal adoption were decisive in setting Japan’s enduring left-hand traffic rule.

How Japan Fits Globally

Roughly a third of the world’s population lives in countries that drive on the left, including the United Kingdom, Ireland, Australia, New Zealand, India, Pakistan, Bangladesh, Thailand, Malaysia, Singapore, Indonesia, and several in Southern Africa. In East Asia, Japan is the prominent left-driving country today; China and both Koreas drive on the right, reflecting different 20th-century influences. Some places formerly administered by Japan (Korea, Taiwan) drove left before switching post-1945.

Practical Implications Today

Modern Japan is fully configured for left-hand traffic: expressways, interchanges, signage, bus doors, and pedestrian interfaces are designed accordingly. Vehicles are right-hand drive, driver training and licensing assume left-side rules, and “keep left, pass right” is the norm on multi-lane roads. The system’s continuity—interrupted only in Okinawa from the late 1940s to 1978—contributes to Japan’s high road-safety performance by minimizing ambiguity.

Summary

Japan drives on the left chiefly because British-guided railways established left-side operation in 1872, a convention that migrated to streets and was formalized by national traffic regulations—most notably in 1924 and retained in postwar law. A brief, local postwar detour in Okinawa aside, the rule has been stable ever since. Samurai-era customs make for engaging lore, but the enduring left-hand system owes most to rail engineering choices and the legal frameworks that locked them in.

Why doesn’t the US drive on the left?

The United States drives on the right because right-hand travel was the norm in Colonial America due to the use of large wagons and practical reasons like ditch avoidance. This custom was codified into law, with New York making it mandatory for public highways in 1804, and it predates the American Revolution, not being an act of rebellion against Britain. 
Early American Practices

• Wagon Drivers: Opens in new tabIn the 18th century, large, heavy freight wagons became popular in the U.S. Drivers often sat on the left rear horse to better manage the team with their right hand and used their right arm to whip the horses, requiring them to keep to the right to avoid ditches and manage the whip more effectively. 
• Right-Handedness: Opens in new tabAs most people are right-handed, keeping to the right also allowed pedestrians and horseback riders to keep their dominant sword arm free for defense against potential threats on the road. 

Legal Standardization 

• Pennsylvania: Opens in new tabThe state of Pennsylvania was an early adopter of right-hand travel, legislating it for its turnpikes in 1792.
• New York: Opens in new tabNew York was the first state to prescribe right-hand travel on all public highways in 1804, establishing a standard that other states soon followed.

Distinction from British and Ancient Traditions

• Colonial Opposition: Right-hand travel in America was not an opposition to British rule but rather a separate path of development. Britain’s left-hand driving law was established in 1773, while right-hand travel had already become the norm in the American colonies. 
• Ancient Origins: While ancient Romans drove on the left, often to keep their sword arm free, early American practices diverged from this due to different transportation methods and societal needs, such as the need to manage large, four-horse teams with a driver seated on the left side of the wagon. 

Why does England drive on the left?

England drives on the left due to its origins as a country where most people were right-handed, favoring a “keep left” tradition to keep their dominant sword hand free to defend against oncoming threats. This practice, already a common custom by the 18th century, was cemented into law with the 1773 General Highways Act to manage growing horse traffic congestion, making left-hand driving mandatory and a precedent for the automobile age. 
Historical Roots

• Medieval Tradition: The tradition likely started in the Middle Ages when most people were right-handed. Travelers on horseback would keep to the left, allowing their right hand, which held their sword, to be free to defend themselves against potential attackers. 
• Roman Influence: Some theories suggest the practice could even date back to Roman times, as chariot riders may have followed a similar left-hand rule. 

Practical Application and Legalization

• Horse-Drawn Carriages: Opens in new tabWhen horse-drawn wagons became more common in the 18th century, the practice of driving on the left became more formalized. 
• Congestion and Safety: Opens in new tabThe 1773 General Highways Act in Britain established the requirement to drive on the left to prevent collisions on increasingly congested roads, particularly in areas like London. 

Legacy and the Spread of the Practice

• Established Convention: By the time automobiles became widespread, left-hand driving was a long-standing and entrenched convention in Britain, making it a natural choice for the new vehicles. 
• British Empire: The practice spread throughout the British Empire, which is why many countries that were once part of the British Empire, such as India, New Zealand, and Australia, continue to drive on the left today. 

Did Canada ever drive on the left side of the road?

Driving in the left lane was the norm on the east and west coasts of Canada, until cross-country jaunts by automobile became more common and the need for standard cross-border traffic rules became more urgent. Central Canada and the prairie provinces had always followed the American practice of driving on the right.

Why does Korea drive on the right?

Korea, meaning the unified Korean peninsula at the time of the change, shifted to driving on the right after 1945 because the American and Russian military vehicles that occupied the roads were designed for right-hand traffic, a legacy of U.S. and French influence, which prevailed over the left-hand driving tradition inherited from Japanese colonial rule.
 
Historical context

• Japanese Influence (driving on the left): During its colonial period, Korea was under Japanese rule, and Japan itself drives on the left due to historical British influence and the construction of its first railway system based on the British model. 
• Post-WWII Transition to Right-Hand Traffic: After the end of the Second World War, Korea was divided into two occupation zones: American and Russian. 
  • American and Russian Vehicles: The presence of American-made and Russian-built vehicles, which are designed for driving on the right side of the road, directly led to the implementation of right-hand driving on the Korean peninsula. 
• Cultural and Political Influence: Countries influenced by the United States, France, or Germany generally adopt right-hand driving systems. Korea’s post-colonial alignment with these influences meant a shift away from its prior left-hand traffic system to the right. 

Summary
The change from left-hand to right-hand driving in Korea was a direct consequence of the American and Russian presence after the Japanese colonial era. The prevalent use of American and Russian vehicles, which were designed for right-hand traffic, directly caused the shift and solidified the right-hand rule for driving on the peninsula.