In an age of seemingly endless wars where nations can no longer even know when they’ve achieved objectives, let alone savor satisfying victories, it’s tempting for military students to look to the past. The pursuit of the 10 massive lesser conquests offers a vivid reminder of how empires rose, fell, and reshaped the world. Historians have drawn us neat, definitive maps and provided clear start‑and‑end dates, but the real allure lies in the vicarious sense of power and accomplishment that comes from walking in the footsteps of the victors.
Why These 10 Massive Lesser Conquests Matter
10 The Rise Of The Parthians
We all know the name Alexander the Great, and as a result, his conquest of the Persian Empire and invasion of the Indian Empire are common knowledge. Much less well‑known is what happened to Alexander’s immense Greco‑Persian Empire after he died in 323 BC without a named heir. Consequently, civil wars broke out which would endure for decades on and off. The most successful of any claimants to the empire was Seleucus I Nicator. By 300 BC, his armies had taken most of modern Turkey through modern Pakistan. Unlike Alexander’s empire, the Seleucid Empire endured for centuries, spreading a religiously tolerant and financially vibrant trade hub. Yet by 247 BC, a kingdom known as the Parthian Empire emerged with its capital in Nisa which over roughly the next 160 years conquered most of the Seleucid Empire. Afterward, the Parthian Empire would become the most prominent force in the Middle East for centuries, eventually falling in 223 AD.
The real enduring relevance of the Parthian Empire was its role as a rival to the Roman Empire. After Parthian armies demonstrated they could annihilate far larger Roman forces at Carrhae in 44 BC, the Parthian Empire took the initiative for eastward expansion away from Rome and spent the next few centuries bleeding Rome white, leaving it vulnerable to such invaders as the Germanic tribes. Although the Roman Empire outlasted it by centuries, the Parthians did as much to bring about Rome’s downfall as any barbarian army.
9 Ashoka The Great
Ashoka took the throne of the Mauryan Empire in 268 BC. He inherited a realm that stretched from the Hindu Kush through much of modern Northern India along the Ganges River to the Subarnarekha River. By the end of Ashoka’s reign in 232 BC, it stretched down all but the tip of the Deccan Peninsula and from the Arabian Sea to the Bay of Bengal. The human toll of this conquest was vast, even by the standards of the time. At the Battle of Kalinga alone, Ashoka’s army was said to have killed 100,000 people while also suffering tremendous losses themselves due to the valor of the Kalingas allowing them to nearly win the day. With those losses in mind, it’s not so surprising that the Mauryans were willing to force a reported 150,000 women and child prisoners into slavery.
Today Ashoka is at least as celebrated for his alleged attempt at redemption after his conquests left such flows of blood in their wake. He greatly improved the infrastructure of the Mauryan Empire (particularly regarding roads). He not only promoted religious tolerance but helped legitize Buddhism. Most important of all, he was credited with laws abolishing slavery during his reign.
8 The Swedish Empire
After staying neutral for World Wars I and II, Sweden isn’t thought of as a military powerhouse. But in the 1600s, Sweden was one of the most prominent powers in Central Europe. Beginning in 1560, Sweden fought several wars with Denmark for dominance of the Baltic Sea and came out massively ahead. By 1618 when Ferdinand II of Bohemia attempted to reinstitute absolute Catholic rule in Central and Eastern Europe, the Swedish military had been honed into a disciplined, well‑compensated, and well‑equipped modern force. It would defeat Poland over a four‑year war from 1625 to 1629, defeat Denmark again, and then win over Germany to reject the authority of the Catholic League. By its height in 1658, Sweden had gained control of most of modern Finland, middle Norway, Estonia, and lucrative territory in modern Northern Germany such as Bremen‑Verden.
Sweden had the good luck of being ruled by a couple of military geniuses. First, there was Gustavus Adolphus, who in addition to his numerous battlefield victories reformed Swedish trade and industry to allow a flow of foreign capital and trade so that Swedish weaponry became the envy of much of Europe. His greatest single victory was at the battle of Breitenfeld in 1631, where his mobile infantry and artillery ruined the previously undefeatable Catholic League army under Count Tilly. It was only his death at his second greatest victory in 1632 at Luetzen that stopped him from creating a pre‑eminent unified German nation centuries early and forming a league with Sweden that could dominate Europe.
After Adolphus came Charles XI. He reformed the entire Swedish government into a combination of absolute monarchy and parliament, which held the economy together and with it Sweden’s many territorial acquisitions, though even Charles XI needed to put down rebellion after rebellion. He also overhauled the Swedish Navy so that it became one of the finest in the world.
7 The Conquest Of The Aztecs And Beyond
Hernán Cortés first arrived in Hispaniola (modern Cuba) in 1504. After rising through the ranks by taking part in the conquest of that island, in 1519 he disobeyed orders from Governor Velázquez and sailed with 500 men and eleven ships to the Mexican mainland. Over the next two years, he forged local alliances through feats of arms among roughly 200 anti‑Aztec communities called the Tlaxcala. With them at his back, in 1519 Cortés’s men entered the Aztec capital of Tenochtitlan under initially cordial terms, only to be forced to seek refuge after the Aztecs soured on the Spanish and attempted to kill them. In 1520 the Tlaxcala sided with Cortés as he confronted rival Conquistador Narváez, who had been sent by Velázquez to displace him. Instead, the Cortés‑Tlaxcala alliance defeated and absorbed the new army, then marched on the Aztec capital again, sacking it in 1521.
This is a well‑covered piece of history, but far less known is what happened next. In 1527, viceroys sent by the Spanish crown to help administer New Spain accused Cortés of poisoning them, forcing him to return to Spain to defend himself. Although acquitted, while he was away he was stripped of his governorship. This was a real pity for the Spanish Empire, as Cortés’s men had been enthusiastically moving through modern Mexico and beginning to settle in Alta California, modern California. However, the initiative for northern expansion was slowed greatly, allowing American settlers to out‑settle and eventually overwhelm Spanish settlers in the 19th Century. Sometimes it doesn’t pay to be a maverick conqueror.
6 The Forging Of The Russian Empire
Today Russia is not only the largest nation in the world, at 6.6 million square miles it’s nearly twice the size of Canada, the second largest. This is a nation that in 1462 when it was known as Muscovy was scarcely larger than modern Germany. How did that happen?
The story of Russia first swelling into a giant power begins with two Ivans. The first was Ivan III who took the throne in 1462 and by the end of his reign had more than tripled the size of the nation by annexing several small principalities and in 1478 annexing the Republic of Novgorod. In 1480, the Mongolian Golden Horde came to confront the rising power and was sent packing.
What’s particularly notable about Ivan III’s successes was how bloodless many of them were. For example, in seizing Novgorod he mostly exploited internal rivalries to win the territory without a major battle. When confronting the Mongols, the Horde’s military was sent retreating without a fight at all. One of his greatest conquests wasn’t another principality; it was the Princess Sofia Paleologue of the Byzantine Empire, offering tremendous wealth and legitimacy to the rising Eastern European power.
Then there was the 1547 ascension of Ivan IV, better known as “the Terrible” for his purges and draconian treatment of rebels. His military career was decidedly mixed, such as the 24‑year‑long Livonian War to conquer modern Estonia and Lithuania, which ended with at best a stalemate and was marked by Moscow being burned. Still, he was successful with major territorial gains such as the major cities across the Volga River (while driving the Mongols away from Astrakhan without a fight) and the first conquests outside of the Slavic areas.
The single largest conquest that expanded the size of Russia began in 1581 when Cossack cavalry under the command of Yermak invaded Siberia. The invasion was retaliation to raids by Mongols under Kuchum as part of an effort to reinstate a great Khanate. Instead of uniting a new empire, Kuchum’s communities fell into infighting, which greatly aided the Russians in the short term as they established forts throughout Siberia, and also left Siberians more amenable to rule from Moscow to end the constant raids on each other. The Russian government immediately incorporated Siberian leaders into the Russian administration instead of treating them as semi‑independent colonies, as European powers often did in the Americas. It also helped that, as with many colonizations, the Russians brought deadly diseases with them. By 1742, the last of the rebel indigenous groups, the Chukchi, was put down. It seems more than the French Empire under Napoleon, the rise of the Russian Empire was characterized by dividing and conquering.
5 Japanese Empire
By 1905, the expansionist ambitions of Japan received massive validation when it destroyed the Russian Navy at the Battle of Tsushima Straits. By 1910, it had added Korea to its holdings. For the next couple of decades there was a lull in new conquests as the Meiji Dynasty dealt with internal matters such as quashing a socialist movement, surviving massive earthquakes, and reorganizing a largely agrarian economy into a more industrial one.
The conquests restarted dramatically in 1931 when, under the pretext that the Chinese military attempted to bomb a civilian train, Japan invaded and annexed the Manchurian Province, a move carried out without approval from the Japanese civilian government. A similarly flimsy pretext—the disappearance of two Japanese soldiers on the border to China—was used in 1937 to justify another Sino‑Japanese War, during which most of the Kiangsu and Inner Mongolian provinces were seized, placing significant cities such as Shanghai, Hong Kong, and the capital Nanking under Japanese control. By 1942, the empire’s high‑water mark included Burma, Thailand, most of Malaysia and Indonesia, and the Philippines. In less than half a century an island nation of fewer than 150,000 people swelled to 2.68 million square miles.
The Japanese Empire was particularly aggressive in cultural erasure. For example in Korea, not only did 100,000 Japanese people move there while many Koreans were taken to Japan, but Korean historical documents were destroyed en masse. Even forests of native Korean trees were clear‑cut so they could be replaced by Japanese trees. Even today, Japan has many descendants of slaves from its imperial age who attempt to conceal their heritage.
4 The Rashidun And Umayyad Caliphates
It can hardly be overstated how much the arrival of Islam energized the Middle East. After the Prophet Muhammad died in 632 AD, the Rashidun Caliphate began when Abu Bakr was elected his successor and finished the conquest of the Arabian Peninsula that the prophet started. He completed the conquest but died in 634. His successor Umar waged war on modern Iran; although assassinated in 644, they conquered Iran by 651 under his successor Uthman, who also took Armenia. Uthman was assassinated in 656, and his successor Ali brought Egypt, Libya, and part of modern Turkey into the fold. This was achieved by a military force that never numbered more than 100,000 troops.
As indicated by the rapid succession of rulers who died shortly after taking power, trouble was brewing from the start. Not only did the Sunni‑Shia split emerge during this period, but Ali was ousted in 661 and replaced by the Umayyad Caliphate. The change in management did nothing to slow expansion. By 700, the Caliphate had conquered modern Tunisia, Algeria, and Morocco in the West. In the East, Afghanistan, Uzbekistan, Turkmenistan were absorbed and India itself was invaded. By 711, the Iberian Peninsula fell, with Portugal and most of Spain under control. It wasn’t until the 732 Battle of Poitiers, a deep raid into France, that the tide began to turn. At its height the Caliphate spanned 5.79 million square miles, approaching a third of the world’s population at the time.
3 Timur The Lame / Tamerlane
It is surprising how little discussed Tamerlane is today despite being a colorful and successful figure in military history. Born in 1336 into a minor noble family in modern‑day Uzbekistan, he collaborated with the Mongols and by 1364 had distinguished himself both as a mercenary and in helping the Mongols conquer Transoxiana. He then joined forces with his brother‑in‑law Amir Husayn and seized Transoxiana for himself by 1366. During this period he received an infected arrow wound that left him unable to use his right arm and leg properly, earning him the nickname “lame.”
Despite betraying a Mongol leader being key to his rise, Tamerlane styled himself as a fusion of Mongol power and Islam, marrying his sister‑in‑law Saray Mulk Khanum, a purported descendant of Genghis Khan. He emulated Mongol reliance on cavalry and treated resisting cities brutally, destroying landmarks in places like Herat while sparing cities such as Tehran. By 1405, his empire encompassed modern Afghanistan, half of modern Pakistan, Turkmenistan, all of Iran, most of Iraq including Baghdad, the Caucasus, and much of western Turkey—demonstrating a working, if ruthless, strategy.
2 The Mongol Empire
TopTenz has devoted lists to the Mongol Empire before, but it’s time for a fresh rundown of their conquests. In 1206, Temujin united the steppe peoples of central Asia, and by 1209 they had conquered Xi Xia, a kingdom on the northern border of China. War with China followed, and by 1215 they had taken the capital Beijing. In 1219 Genghis Khan’s wrath moved west when the Khwarezm Empire (modern Kazakhstan, Uzbekistan, Iran) insulted the Khanate by attacking a protected caravan and murdering the Mongol emissary. Genghis died in 1227, four years before the Mongols completed crushing Khwarezm. He was still alive when the Mongols entered modern Russian territory in 1223, launching a remarkably successful campaign even by Mongol standards.
By 1240 the Mongols added most of modern Russia and Ukraine, most notably sacking Kyiv. In 1242 they invaded modern Eastern Europe, including Poland and Bulgaria. A conveniently timed death of Khan Ogedei spared much of central Europe from Mongol domination. By 1258 they turned their sights to the Middle East, conquering Baghdad in a particularly horrific manner. In 1260 they were thoroughly repulsed in Egypt for the first time, and subsequent defeats in Vietnam and Japan turned the tide against them. At its height the empire spanned 12 million square miles, unquestionably the largest contiguous empire in world history.
1 The “Sun Never Sets” Empires
The United Kingdom was not the first empire to claim that the sun never set on its territories. The Portuguese Empire reached that milestone first, with colonies in Africa, India, and the Portuguese East Indies thanks to Vasco da Gama’s 1497 voyage and the 1500 founding of Brazil. It was later eclipsed by the rise of the Spanish Empire under the notoriously incestuous Philip II, which, after conquering the Aztecs, controlled vast swaths of North and South America, Equatorial Guinea in Africa, the Philippines, the Canary, Mariana, and Caroline Islands, and even portions of Italy, Austria, and the Netherlands. Unfortunately for Spain, Philip II’s disastrous 1588 launch of the Spanish Armada into the English Channel resulted in a catastrophic defeat that cost half the 130‑ship fleet, swinging initiative massively to Britain’s favor.
Control of India began in the 1600s, with the acquisition of major trading centers Madras in 1639 and Bombay by 1661. In 1763 the Treaty of Paris at the end of the French‑Indian War yielded control of Canada and gave the kingdom massive holdings in North America even after the American colonies left in 1783. Around that time in 1788, 736 convicts were landed in Australia. In Africa, colonization started in 1787 when 300 freed slaves loyal to Britain during the American Revolution and 70 white prostitutes were landed in Sierra Leone. From that awkward beginning, control expanded to include lands from South Africa in 1820 to Egypt by 1899. By 1841 Britain had acquired the lucrative islands of Hong Kong and Taiwan. By the time Britain reached its greatest size in 1920, with territorial concessions from Germany and the Ottoman Empire, it spanned 13.71 million miles, and 412 million people—a quarter of the world’s population—lived within its borders. Let’s hope we never see another nation try to top that.