The Russo-Japanese War was a military conflict fought between the Russian Empire and the Empire of Japan from 1904 to 1905. Much of the fighting took place in what is now northeastern China. The Russo-Japanese War was also a naval conflict, with ships exchanging fire in the waters surrounding the Korean peninsula. The brutal conflict in the western Pacific, which was resolved with the Treaty of Portsmouth, changed the balance of power in Asia and helped to set the stage for World War I.

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‘World War Zero’

Russia was already a significant world power in the early 20th century, with vast territories in Eastern Europe and central Asia under its control, and Japan was widely viewed as the dominant force in Asia at the time.

Therefore, the war garnered significant global attention and its ramifications were felt long after the final shot was fired in 1905.

In fact, scholars have suggested that the Russo-Japanese War set the stage for World War I and, ultimately, World War II, as some of the central issues in the first conflict were at the core of the fighting during the latter two. Some have even referred to it as “World War Zero,” given that it took place less than a decade before the start of World War I.

What Started the Russo-Japanese War?

In 1904, the Russian Empire, ruled by the autocratic Czar Nicholas II, was one of the largest territorial powers in the world. However, with the Siberian shipping center of Vladivostok forced to close for much of the winter months, the empire was in need of a warm-water port in the Pacific Ocean, both for purposes of trade as well as a base for its growing navy.

Czar Nicholas set his sights on the Korean and Liaodong peninsulas, the latter located in present-day China. The Russian Empire already leased a port on the Liaodong Peninsula from China—Port Arthur—but it wanted to have a base of operations firmly under its control.

The Japanese, meanwhile, had been concerned about Russian influence in the region since the First Sino-Japanese War of 1895. Russia provided military support to the Qing Dynasty in China during that conflict, which pitted the two Asian powers against each other.

With the Russians’ history of military aggression, the Japanese initially sought a deal, offering to cede control of Manchuria (northeastern China). Under the terms of the proposal, Japan would have maintained influence over Korea.

However, Russia refused Japan’s offer and demanded that Korea north of the 39th parallel serve as a neutral zone. As negotiations broke down, the Japanese opted to go to war, staging a surprise attack on the Russian navy at Port Arthur on February 8, 1904.

Russo-Japanese War Begins

Japan formally declared war against Russia on the day of the Port Arthur attack. But leaders of the Russian Empire did not receive notice of Japan’s intentions until several hours after the Asian power had attacked Port Arthur, which served as the Russian navy’s base of operations in the region.

Czar Nicholas had been told by his advisors that the Japanese would not challenge Russia militarily, even after negotiations between the two powers had collapsed.

Notably, international law did not require a formal declaration of war prior to launching an attack until the Second Hague Peace Conference of 1907, two years after fighting between the Russians and Japanese had ended.

Battle of Port Arthur

The attack by the Japanese Imperial Navy against the Russian Far East Fleet at Port Arthur was designed to neutralize the Russians.

Under the leadership of Admiral Togo Heihachiro, the Japanese Imperial Navy sent torpedo boats to attack Russian naval vessels, significantly damaging three of the largest: Tsesarevich, Retvizan, and Pallada.

The ensuing Battle of Port Arthur began the next day. Although the rest of the Russian Far East Fleet was largely protected within the harbor at Port Arthur, the attacks successfully dissuaded the Russians from taking the battle to the open seas, even though attempts to establish a Japanese blockade of the port failed.

However, the Russian ships that evaded the Japanese did not escape unscathed. On April 12, 1904, the Petropavlovsk and Pobeda battleships were able to leave Port Arthur but struck mines just after making it out to sea. Petropavlovsk sank, while Pobeda limped back to port heavily damaged.

While Russia avenged that attack with mines of its own, severely damaging two Japanese battleships, the Asian power retained the upper hand at Port Arthur, continuing to bombard the harbor with heavy shelling.

Battle of Liaoyang

After attempts to attack Russian fortifications on land failed, resulting in significant casualties for the Japanese, the Asian power’s persistence eventually paid off.

In late August, forces from northern Russia sent to assist the fleet at Port Arthur were pushed back by the Japanese at the Battle of Liaoyang. And, from newly gained positions on land in the vicinity of the harbor, Japanese guns fired relentlessly on Russian ships moored in the bay.

By the end of 1904, the Japanese navy had sunk every ship in Russia’s Pacific fleet, and had gained control of its garrison on a hill overlooking the harbor.

In early January 1905, Russian Major General Anatoly Stessel, commander of the Port Arthur garrison, decided to surrender, much to the surprise of both the Japanese and his bosses in Moscow, believing that the harbor was no longer worth defending in the face of humiliating losses.

With that, the Japanese had achieved a significant victory in the war. Stessel was later convicted of treason and sentenced to death for his decision, though he was ultimately pardoned.

The Russian Navy later sustained heavy losses during the Battle of the Yellow Sea, forcing the empire’s leaders to mobilize their Baltic Fleet to the region as reinforcements.

Russo-Japanese War in Manchuria and Korea

With the Russians distracted and demoralized, Japanese ground forces set about controlling the Korean peninsula after landing at Incheon in modern-day South Korea. Within two months, they had taken over Seoul and the rest of the peninsula.

At the end of April 1904, Japanese ground forces began planning an attack on Russian-controlled Manchuria in northeastern China. During the first major land battle of the war, the Battle of Yalu River, the Japanese mounted a successful attack against the Russian Eastern Detachment in May 1904, forcing them to retreat back toward Port Arthur.

With fighting intermittent during the Manchurian winter, the next notable land battle in the conflict began on February 20, 1905, when the Japanese forces attacked the Russians at Mukden. Days of harsh fighting ensued.

Able to push back the Russians at the flanks, the Japanese eventually forced them into full retreat. On March 10, after three weeks of fighting, the Russians suffered significant casualties and were pushed back to northern Mukden.

Tsushima Straits

Although the Japanese had achieved an important victory during the Battle of Mukden, they too sustained significant casualties. Ultimately, it was their navy that would win them the war.

With Russia’s Baltic Fleet finally arriving as reinforcements in May 1905, after sailing nearly 20,000 nautical miles—a monumental task, especially in the early 1900s—they still faced the daunting challenge of having to navigate the Sea of Japan to get to Vladivostok, with Port Arthur no longer open to them.

Opting to sail at night to avoid detection, the Russian reinforcements were soon discovered by the Japanese, after its hospital ships opted to burn their lights in the darkness. Again under the command of Admiral Togo Heihachiro, the Japanese navy attempted to block the Russians’ path to Vladivostok and engaged them in battle at the Tsushima Straits late on May 27, 1905.

By the end of the next day, the Russians had lost eight battleships and more than 5,000 men. Only three vessels ultimately made it to their destination. The decisive victory forced the Russians to pursue a peace agreement.

Treaty of Portsmouth

In the end, the Russo-Japanese War was a particularly brutal one, foreshadowing the global conflicts that were to follow. It’s believed that both sides sustained casualties mounting to more than 150,000 combined, and that some 20,000 Chinese civilians were killed as well.

Many of these civilian deaths were attributed to the harsh tactics of the Russians in Manchuria. Journalists covering the war suggested that the Russians looted and burned several villages, and raped and killed many of the women living there.

The fighting concluded with the Treaty of Portsmouth, which was mediated by U.S. President Theodore Roosevelt at Portsmouth, New Hampshire, during the spring and summer of 1905.

Negotiating for Russia was Sergei Witte, a minister in Czar Nicholas’ government. Harvard graduate Baron Komura represented Japan. Roosevelt was awarded the Nobel Peace Prize for his role in the talks.

Aftermath of the Russo-Japanese War

Although Japan had won the war decisively, victory had come at a severe cost: the country’s coffers were virtually empty.

As a result, Japan did not have the negotiating power many expected. Under the terms of the treaty, which was signed by both parties on September 5, 1905, Russia turned over Port Arthur to the Japanese, while retaining the northern half of Sakhalin Island, which lies off its Pacific coast (they would gain control of the southern half in the aftermath of World War II).

Importantly, Roosevelt sided with Czar Nicholas in his refusal to pay indemnities to Japan. The Japanese accused the Americans of cheating them, and days of anti-American rioting in Tokyo ensued. The Asian nation would later question America’s role in Asian affairs during the lead-up to World War II.

The Russians also agreed to leave Manchuria and recognize Japanese control of the Korean peninsula. The Empire of Japan would annex Korea five years later, an act that would have important repercussions during and after World War II.

Russo-Japanese War Legacy

The costly and humiliating series of Russian defeats in the Russo-Japanese War left the Russian Empire demoralized, added to Russians’ growing anger at the failed policies of Czar Nicholas II, and would fan the flames of political dissent that ultimately resulted in the overthrow of the government during the Russian Revolution of 1917.

Although tensions in the region were far from over, the Russo-Japanese War did shift the balance of global power, marking the first time in modern history that an Asian nation had defeated a European one in military combat. It would also mark the beginning of warfare involving global powers in the Pacific region.


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