The First World War saw battles throughout Europe, as it was mostly European powers at war, but those powers also had far-reaching empires. It is, perhaps, more well-known that the theaters of war during World War II were not solely relegated to the European continent. It was, in many ways, the more prominent global war. Both, however, were world wars. How were countries outside of Europe involved in both conflicts and what sets both apart as true world wars?

What Makes a War a World War?

The term “world war” was first used in English by the Oxford English Dictionary in 1848. A Scottish newspaper called The People’s Journal reported, “A war among the great powers is now necessarily a world war.” The phrase was then further used by Karl Marx as well as several other authors who described various conflicts, both fictional and real, as world wars.

World War I was first coined as such by Time Magazine in 1939. Furthermore, the same issue of the magazine speculatively states that “World War II” would follow the first. Several other languages soon took up the terminology, and it has been used ever since to describe the two most global conflicts in our recent history.

But why were they dubbed world wars to begin with? To answer this, we must look at both wars individually, as the reasoning for their titles is slightly different.

Colonial holdings played a huge role in the war, both as a source of men and supplies as well as a potential arena of attack. The First World War created a domino effect involving several nations due to imperialism and saw war on a global stage that would not have been feasible earlier in its history.

World War II was dubbed with the title for a few different reasons. First, the established theaters of war and the powers that fought were not solely European; in fact, a major theater of the war was not, for the majority, fought between European powers. The Allies and the Axis powers were made up of a wider reach of nations, with a broader scope of locations serving as battlefields. Second, World War II was named as such because of the incredibly profound impact that the war had on world history.

World War II saw the deaths of around 75 million people, of whom 20 million were troops and about 40 million were civilians. The nearly unfathomable death toll, mainly the result of genocide and mass murder, was a shock to the human population. In addition to the loss of life, empires crumbled and never recovered. Additionally, two major powers arose from the conflict, namely the Soviet Union and the United States, the likes of which had not been seen in the modern world thus far. The global historical impact of World War II is incalculable, and as such, the title of world war fits well.

World War I: Who Fought?

Two alliances formed the opposing sides in World War I. First were the Central Powers, formed by Germany, Austro-Hungary, and the Ottoman Empire. The Entente powers were made up of France, Russia, Portugal, Belgium, Serbia, Italy, Britain, and, eventually, the United States, Japan, and Brazil.

When the war broke out, the British Empire was the largest in the world. Its colonies in North America, the Caribbean, Oceania, South Asia, and Africa numbered a population of 412 million. Only 44 million of this population were actually British citizens, while 80% of them were Indian. The British called upon its colonies for troops and supplies, enlisting more than 1.2 million Indian soldiers, 54,000 troops and laborers from Nigeria, 332,000 soldiers from Canada, and 444,000 more soldiers from Australia and New Zealand.

The other Entente powers brought manpower from their colonies as well. France’s troops from Africa numbered 335,000, and from Vietnam, 50,000. Russia, with its vast swath of land stretching to the Pacific Ocean, drew from troops in Central Asia and Siberia. Eventually, American troops in the war numbered around 2,000,000. Even neutral powers like China supported the efforts of the Entente with more than 120,000 laborers.

The Central powers involved their colonies as well, like the Ottomans, who drew from Arabia, but the global effort of the Entente was greater and possibly helped to win the war for the powers.

World War I: Where was the Fighting?

Problems within Europe were the reasons for war in the first place, but many battles were fought in a sort of proxy, whether the colonized fought on behalf of the empire or if the empire fought to gain new global territory. However, most battles of World War I took place on three fronts in Europe: the Eastern Front of the Russian border, the Western Front in France and Belgium, and the Italian-Austro-Hungarian border with the Balkan states.

In Africa, some of the earliest battles of the Great War (as it was known then) took place before fighting even began in Europe. Notably, these battles often occurred as offensives of British colonial troops invading German colonies. This was the case in Togo (then called Togoland) and Cameroon (then the German colony of Kamerun), which fell quite quickly due to their smaller populations of Germans. In German South-West (Namibia) and East (Tanzania) Africa, the capture was not so easily won by the Entente.

In 1915, modern-day Namibia was invaded by South African troops (a British colonial force) and battled for several months with a large number of German troops there, finally taking the capital of Windhoek. In modern-day Tanzania, British and German forces clashed for the entire duration of the war, and no one prevailed in the battle. In fact, the fighting in German East Africa would not cease until three days after the armistice of November 1918.

In Asia, several German outposts, including Western Samoa, Micronesia, the Marshall Islands, and German New Guinea, were captured by Entente forces, mainly from Australia and New Zealand. The Central and Entente powers also fought brutal naval battles throughout the Indian and Pacific Oceans. However, Germany’s main worry was their holdings in China, which they eventually surrendered to a British ally, the Japanese Empire.

In the Middle East, most of the fighting of the First World War was centered around the Suez Canal. The Central Powers sought to place the Ottoman Empire’s troops in the canal, creating Central strongholds along one of the most used naval thoroughfares in the Middle East. However, before the Ottomans could take the Suez, intense battles with the Entente in the Egyptian Sinai Peninsula drove the Central Powers north and out of reach of the canal.

Another major theater of the Middle East was Palestine, where major battles occurred at Gaza and Beersheba, which drove the Ottoman Empire further north into Turkey. This allowed British strongholds in the Middle East, which would eventually lead to mandates of the empire that would form the modern states of Jordan and Syria.

The New World was also not exempt from action during the First World War. Germany, in an attempt to goad the United States into war with Mexico, offered allyship to the United States’ southern neighbor. Instead of convincing the American army to attack Mexico, however, the United States declared war on Germany and joined the Entente effort in 1917.

These are only a few examples of the proxy battles of World War I, as, by 1918, hostile action had occurred in over 40 countries, with more than 100 nations issuing declarations of war on both sides. Thus, the First World War undoubtedly became the most globally involved war in modern history until its successor.

World War II: Who Fought? 

The combatants in World War II were made up of 50 countries and almost 100 million soldiers. The main powers were the Axis and the Allies. The Axis was originally made up of Germany, Japan, and Italy, while the Allies were initially France, Poland (until both were invaded by the Nazis), and the United Kingdom. Days after the UK joined the Allies, the British independent territories of Canada, Australia, New Zealand, and South Africa also declared war on Germany.

Two large powers that, at first, chose to remain neutral were the Soviet Union and the United States. However, after the German invasion of Russia (violating an act of non-aggression between the two nations) and the Japanese attack on Pearl Harbor, the superpowers had no choice but to enter into the conflict. The “Big Three” of the Allies then became the Soviet Union, the United Kingdom, and the United States. To a lesser extent, China was also a member of the Allies, as they had been at war with Japan since 1937. The Chinese fought largely, as could be expected, on the Pacific Front of the war.

The Axis powers formed as a result of the Tripartite Pact of 1940. This brought the three fascist governments of Italy and Japan into the fray with Hitler’s Germany. Additionally, the Axis was joined by Hungary, Slovakia, Romania, and Bulgaria, the latter of the two later switching to the Allies when it became clear that the Axis would be overpowered.

Along with the signatories of the Tripartite Pact were about 15 other nations, many of whom, especially outside of Europe, were simply puppet states controlled by the Japanese Empire. Countries were also split down the middle, such as India and Vietnam, where two different parties supported different sides. In addition to confused borders and allegiances, many powers originally aligned with the Axis powers later switched sides during the war. There were several reasons for this, but most switched sides due to the apparent uphill battle Germany and the Axis were facing by 1944.

Thus, dozens of countries throughout Europe, as well as many outside of Europe, joined either side of the struggle, making it the largest war in history to date.

World War II: The Pacific Front

Perhaps the most recognizable facet of the war outside of Europe was the Pacific Front, fought predominantly against the Japanese Empire on the part of the Allies outside Europe. The Japanese had already been fighting a war against China, one of the Allied Powers, since 1937, and by the time 1941 rolled around, the Japanese had invaded French Indochina (modern-day Cambodia, Laos, and Vietnam).

The catalyst for the majority of fighting in the Pacific Theater, however, occurred on December 7, 1941. Japan, without any declaration of war, carried out a surprise attack on the US Naval fleet stationed at Pearl Harbor, Hawaii. The attack destroyed a major part of the United States fleet of battleships and prevented them from suddenly interfering with Japanese military operations. The United States responded by declaring war first on Japan and, a few days later, on Germany and Italy.

The Japanese army steamrolled through Asia throughout the rest of 1941 and into early 1942. In December alone, the Japanese Empire took Guam, Wake Island, and Hong Kong, moving on to the Philippines, Indonesia, Malaya, Singapore, and neutral Thailand in the first half of 1942. In mid-1942, the tides were finally starting to turn as British forces in India and Australian and New Zealander forces in New Guinea were able to halt the Japanese from further invasion.

The most decisive turn in favor of the Allies came in June 1942 with the Battle of Midway. The American navy forced Japan to retreat with heavy losses, and the Allies were then able to begin retaking territory island by island. Despite the Allied victories in many of the islands of the Pacific, the Japanese were able to hold their territories on mainland China until 1945.

British and American forces retook the Philippines, Burma, and the strategic Japanese island of Okinawa from October 1944 to June 1945. While both sides suffered heavy casualties during this time, especially at the Battles of Iwo Jima and Okinawa, the Japanese would not surrender and kept fighting to their detriment.

This led to the United States’ strategic bombing plan of August 1945. Two atomic bombs were dropped on the Japanese cities of Hiroshima and Nagasaki on August 6th and 9th, respectively, killing an estimated 120,000 civilians in the process. Less than a week later, the Japanese surrendered to the United States and the other Allied Powers, and the war in the Pacific was won.

World War II: Other Major Arenas Outside of Europe

While the Pacific Front is certainly the most famous theater of war outside of Europe, several other places were battlegrounds on other continents throughout the world. Northern Africa, in particular, played host to a number of battles throughout the war, as did the Middle East.

The African Front of World War II was first focused on Eastern Africa and then, later in the war, on Northern Africa. The Eastern African front was brought into play when Italy attacked a Royal Air Force Base in Kenya. The Italians and British continued this air war until November 1941, when after being driven from Kenya, Sudan, Somaliland, Eritrea, and Ethiopia, the Italian forces surrendered. It was one of the first decisive Allied victories of the war, though fighting in Ethiopia continued until an armistice in 1943 ended the war between Italy and the Allies.

In North Africa, the situation began to show signs of turning the war in favor of the Allies. The Italians had been pushed out of British-occupied Egypt when Hitler sent his forces into Africa led by General Rommel, who kept the British at bay for around 18 months until the battle at El Alamein, as well as the United States Operation Torch, which surrounded the Axis troops and forced surrender in May 1943.

In the Middle East, the fighting centered on Iraq, Iran (then known as Persia), and Vichy France’s holdings in Syria and Lebanon. In Iraq, the Italian government, and later the German government, supported independence for the country, and bolstered by this, the Pro-British monarchy of Iraq was overthrown. In the Battle at Habbaniya, Iraqi forces besieged an RAF base but were quickly defeated due to inexperience. The leader of the Iraqi separatist movement, Rashid Ali, was deposed. Britain was able to once again install a pro-British monarchy under the rule of Faisal II in May of 1941.

The failed rebellion in Iraq furthered the deterioration of relations between Vichy France and Britain in 1941, culminating in the Syria-Lebanon campaign of the same year. In June, the British, Australian, Free French, and Indian units invaded Syria from Palestine in Operation Exporter. In July, with Damascus and Palmyra in Allied hands, British-Iraqi forces had begun moving toward Aleppo, with Australian forces heading toward Beirut. Before the Allies could reach either, however, negotiations for an armistice began. Vichy France surrendered to the British and Free French forces a little over one month after the campaign began on July 11th.

In Iran, the Shah was nominally neutral, but in practice, it was quite well-known that he was pro-Axis. The Shah refused to open Iran as a supply route for Allied forces to the USSR, and subsequently, the country was occupied. The Shah was deposed in favor of his son, who headed the Allies’ puppet government, allowing access to oil and supply routes for the remainder of the war.

In all, many campaigns were waged outside of Europe, but the factor that linked each campaign was an empire. Thus, in the wake of the collapse of the Axis powers, and with the end of the war, came an intense dislike for imperialism and a surge of movements for independence outside of Europe in its largest powers’ proxy states.