10 Largest and Most Powerful Military Forces in Ancient and Modern History

It would be impossible to determine which military force in history would be considered the most powerful. Could it be the Spartans and their apocryphal 300 men who held off the Persian army? Or the Mongols, whose great numbers swept the world while the larger Chinese army stayed home? It could very well be Alexander the Great’s, who only turned back at the Euphrates when his men were tired and homesick.

It is a little simpler to determine the largest armies. This list takes us through history to examine the largest armies during each period.

It is important when looking at them, we consider the world’s population, as well as the population of the country the army grew from. For example, nearly 1% of the Ming Dynasty were active soldiers, the same as if the modern US military was three times bigger than it is today. 

1. The Uruks of Mesopotamia

From 4100-2900 BCE, Mesopotamia and the middle east went through the Urik Period. It was named after one of the first “cities” of the Middle East, Urik, which King Enmerkar founded. It is believed that the word “Urik” would slowly evolve into the Aramaic word “Erech” and eventually the English word “Iraq.”

Urik is famous for its later king, Gilgamesh, the first Ziggaruts, and the “cylinder seal” (used for the first signatures). At its height, it is believed that the empire had an army of four thousand troops or five percent of its people. This army would be made of troops of 50-100 men, who would be armed with spears and axes, wearing helms of bronze and cloaks with bonze discs sewn into them. These troops may have fought battles in modern Syria but had difficulty maintaining control over places so far away.

While the empire was short-lived, the city remained important for four thousand years under the Akkadians, Assyrians, Babylonians, and eventually the Greeks. However, due to droughts and possibly the ever-changing currents of the Euphrates, by 700 AD, the city was abandoned entirely. While never technically lost, it was first properly explored again in 1849.   

2. The Xia Dynasty

While China may have had troops before Uruk, the first recorded army was that of the Xia Dynasty, around 2000 BCE. Vastly superior to the Mesopotamian armies, it numbered twelve thousand men.

Traditional accounts of the time indicate that the soldiers of this army were not just well-trained but also used for non-military purposes. Most famously, Emperor Yu the Great put his troops to work building canals to stop the continued flooding of the Yellow River. 

The only military conflict we know of was the battle against the Sanmiao tribe, which was highly one-sided. The army pushed them south of the Han river, leaving them in exile. This act cemented Yu’s place as the emperor of the first Chinese Dynasty.  

3. The Ancient Egyptian Army

The first army to amass over a hundred thousand men was that of Ramesses the Great around 1250 BCE. The Egyptian Pharaoh was engaged in many battles during his time, including a twenty-year war against the Hittites.

As well as his army, Ramesses had an impressive navy, and his first military victory was over pirates who had been attacking his trading vessels along the north coast.

There is archeological evidence that many of these pirates mutinied and joined the Egyptians, eventually becoming a part of the army. This army would subsequently extend into Libya, Numibia, and the Levant.

4. The Persian Empire

By around 500 BCE, the predominant empire in the world was the Persians. According to many texts, Cyrus the Great was the leader of an army of over 500 thousand in number. These included spearmen, archers, chariots, and mounted cavalry. The empire also used “shield-bearers,” who would form a temporary but effective wall for archers to fire from behind. Then thousand of these soldiers would receive extra training, becoming the world’s first “special forces.” Over time, these soldiers developed the moniker “the Immortals.”

This army was, of course, necessary. The Achaemenid Empire of Cyrus was so great that it covered an estimated forty-four percent of all living peoples on earth at the time. It spanned 5.5 million square kilometers across the globe.

This army likely grew over the decades. According to Herodotus, Cyrus’ grandson, Xerxes I, took over one million men with him into battle against the Greeks. However, less than a hundred years after the empire’s founding, Xerxes was assassinated. Under Alexander the Great, the Greeks would eventually conquer the Persian Kingdom by 330 BCE.

5. The Mauryan Empire

The iron-age empire of Chandragupta Maurya and his sons ruled over India and its surrounds from 322 BCE to 185 BCE. To create this massive empire, Maurya needed to raise an army to attack the northern empire of Nanda. According to traditional Indian literature, the army included six hundred thousand infantry, nine thousand elephants, and another thirty-thousand cavalry.

The exact details of Maurya’s campaign are unknown. Some texts claim that the capital of the Nanda empire fell quickly, while others say the capital itself never fell. With the death of Alexander the Great, Maurya also pushed west before making a treaty with Seleucus; the King would give up land to Maurya in return for soldiers and elephants to fight on his western front.

Maurya’s army grew to a large size partly due to innovative concepts such as the centralization of taxes and a national currency, which made it easier to ensure soldiers were always paid for their work and remained loyal. Maurya also had a vast spy network, and Ashoka (Chandragupta’s son) would utilize it to watch the long borders between the empire and its possible enemies.  

6. The Ming Dynasty

In 1500, the Ming Dynasty of China had between 60 and 150 Million people. This range is difficult to narrow further due to the lack of census taking of civilians. However, at the same time, it is recorded that military members of the Dynasty numbered over 1.3 Million. This appears to be the first time humanity saw a country with an army over one million in strength.

The Ming Dynasty relied heavily on Archers and Cavalry, and soldiers would join Battalions based on family lines. Approximately 20% of families in China were known as “Military Houses.” These families were legally obligated to provide one male as a soldier for China. If this soldier died or was wounded too severely to fight, the family would need to provide another. In this way, the army would always be large, and no family would lose all its men. 

Unlike many other armies in history, the soldiers of the Ming Dynasty were considered low on the societal ladder. There was little prestige to being a soldier, and society viewed a “military family” with disdain. Soldiers would be given a spear or saber. During this period, archers were in high demand and began to be trained in riflery. 

The Ming Dynasty also had a small navy with fifty warships. Some academics have presented the soldiers of the navy as the first example of military units that relied on firearms, as soldiers rarely carried any other weapon. 

7. The French Empire

On the other side of the world to China, it took much longer for the next giant leap in military power to occur. However, the might of the French Empire at the beginning of the 19th century would be impressive.

The Napoleanic Era, between when Napolean performed a coup d’etat and became dictator in 1799 and when he lost the battle of Waterloo in 1815, is now considered one of the most critical periods in French history. Marking the end of the French Revolution, Napoleon’s reign brought a short time of stability to the nation and its colonies, created the “Civil Code,” and formally developed an army from conscripted untrained farmers. This army was two million in size in a country of thirty million people.

The army fought many wars over its short period under Napolean. The Egyptian campaign allowed for scientific and archeological studies, while Napolean also fought multiple “coalitions” of European countries who aligned themselves against his empire.

Unfortunately, the fall of the army and the empire came after a disastrous decision to invade Russia in the winter of 1812. With six hundred thousand of his men, Napoleon planned on pushing the Russian forces back so that Britain would lose trade routes to the rest of the world. However, the self-proclaimed “Emperor of France” lost over half his troops to starvation, hypothermia, and disease within six weeks. By the end of the sixth month, it is estimated that only one-quarter of the army had survived. 

8. German Third Reich (1935-1945)

Throughout the decade known as “The Third Reich,” over thirteen million germans were to take positions in the military.

More importantly, however, it was the only country in Europe to have a dedicated armored (or “panzer”) division that learned tank-specific strategies and the most technologically advanced air force in the world. Germany also had better-trained troops. Modern military thinkers have claimed that, for every two german soldiers, America would require three to have an even battle.

Few people believe Germany’s military might have failed them during World War Two. Instead, it was the crazed strategies of its highest leaders, the dogged attempts at expansion at any cost, and the lack of solid allies that would lead to its downfall.

9. The United States Army (World War II)

By 1945, The US had formed the largest military force in the history of humanity, with a massive 12.2 Million soldiers. This number has not been reached since.

The United States entered World War Two later than many other countries and only properly started amassing a large military after the bombing of Pearl Harbor in 1941. However, the response of the people in the country.

While military conscription existed since 1940, many men and women of the military would have volunteered anyway. Of ten million conscripted soldiers, only sixteen thousand would be found guilty of evasion. Of forty-three thousand conscientious objectors, over half still joined the military in non-combatant roles.

The number of soldiers in 1945 is made all the more impressive by the knowledge that the country had already sustained the vast majority of its casualties. Over 124 thousand American soldiers were wounded or killed on D-Day or during its subsequent operations. That was more than one percent of the entire military.

The might of the American military came not just from its men. From the M1 rifle and 1911 pistol to the Bazooka, the small arms of the American forces were far superior to any other country. At home, the scientific minds of the country were working on even greater weapons, including those that would change the face of warfare forever.

On the 6th of August, 1945, The US Military dropped the first nuclear weapon onto the City of Hiroshima, killing around a hundred thousand people. Only 20% were soldiers. Three days later, the US bombed Nagasaki, which became the only two times nuclear weapons have been used in military warfare.

10. North Korea (Modern Day)

With the largest proportion of the army to the population at any moment in human history, the Korean People’s Army (of North Korea) has approximately nine million members. Armed forces membership is compulsory for all males who do not have an exemption and about one in nine females.

All men over 14 must register for conscription, with health checks every year until they are seventeen. They are legally obligated to spend the next ten years in the army. This includes training as soldiers and working on farms and in factories owned by the government. While this may sound like the national service of other countries, it is essential to recognize that all conscripts are trained for battle and, according to US government reports, are “well versed in the basics even under adverse conditions.”

Beyond this manpower, it is believed that North Korea has approximately forty submarines, 730 combat aircraft, and over 4000 tanks. It often performs “tests” of ballistic missiles and is nuclear-capable. All in all, the North Korean forces, while small compared to larger countries, are powerful and far more extensive than any other country of its size. 

Conclusion

The number of people in any army has continued to grow, as you would expect with humanity’s population. However, with the increase in military technologies, we may have reached our peak in 1945. 

The strength of the military will, however, always be far more challenging to determine. At each new stage of military history, we see a sudden rise in soldier numbers and a change in battle tactics. Navies (and now the air force) have been of vital importance at every point in time, while each military recognized the power of moving quickly between areas of war and attacking from a distance.

Could the giant French army have survived against the much smaller Ming Dynasty fighting in China? Would the German army be the most powerful if not run by those who wanted to rule the world? These are questions best left to the imagination.