The 21 Longest Wars in History Were Brutal Conflicts

Longest wars in history

The 21 Longest Wars in History Were Brutal Conflicts

Key Points

  • The Crusades, which took place from 1096 to 1291, had a significant impact on Europe and the Middle East.
  • The Roman Conquest of the Iberian Peninsula, which lasted from 218 BCE to 19 CE, resulted in the complete annexation of the region by the Roman Republic.
  • The Reconquista, lasting from 718 to 1492, saw Spain become a Christian kingdom once again after almost 1000 years of conflict.

What are the longest wars in history? Recorded history is littered with stories of conflict and warfare. The sheer brutality and scale of some of these conflicts have to be seen to be truly believed. Today’s guide is focusing on the longest wars in human history. These aren’t typical affairs like The Great War or the Second World War.

Instead, these are conflicts that span significant amounts of time. The wars covered in today’s guide easily exceed a few years, with some lasting centuries. If you’re a military history buff, buckle up, because we’re doing a deeper dive into some of the most brutal conflicts recorded.

Aceh War

longest wars in history
The Aceh War is noteworthy for being one of the earliest wars to have a deluge of photographs documenting the conflict.

To kick things off with the longest wars in history, it’s worth taking a closer look at the Aceh War. The conflict itself began in 1873 and lasted until 1904 — around 31 years in total. This is one of the first true modern conflicts and saw the advent of photographs to bring the conflict’s horrors abroad.

The political reasons behind the war itself are a little more nebulous. Aceh was guaranteed sovereignty and independence under the Anglo-Dutch Treaty of 1824. The opening of the Suez Canal in 1869 would start to stoke the fires which would lead to open conflict. Imperialism was still the rule of the day circa the late 19th century.

As such, when Dutch interests in Southeast Asia began, a bloody conflict was in the works. This did much to shape the current geopolitical climate in Southeast Asia, and Aceh would ultimately fall to Dutch rule. The Aceh Sultanate would eventually become modern-day Indonesia, but not before around 100,000 casualties would be inflicted.

Open conflict itself ended in 1904, but insurgent attacks persisted until the end of the Second World War.

Ayutthaya-Lan Na War

the longest wars in history
What began as a border conflict would end as a stalemate with little ground gained or lost.

With an overall duration of 33 years, the Ayutthaya-Lan Na War is one of the longest in recorded history. The actual conflict itself ran from 1441 to 1474. Participants were the Ayutthaya Kingdom, located in the southwest of modern Thailand, and the Lan Na Kingdom which was also in Thailand.

Like many conflicts, this started as a border dispute. You’ll see this time and time again before modern nation-states unified. War brewed due to the machinations of the governor of Muong Terng, who urged Ayutthaya powers to invade Lan Na.

This incited a massive war without much in the way of territory lost or gained. The conflict itself ended in a stalemate, with Lan Wa coming away with a bit more land than before. However, the long duration and expenses of the conflict would end up severely weakening the Lan Wa Kingdom.

Guatemalan Civil War

the longest wars in history
The civil war in Guatemala was a long-lasting conflict that is still being felt in the country today.

This is arguably one of the most recent entries in our list. The Guatemalan Civil War started in 1960 and ended in 1996, marking this as one of the longest wars in history. Open war was waged by the government of Guatemala and various rebel groups.

The Guatemalan Civil War is a highly contentious conflict, and the aftershocks of the war can still be felt. While Guatemala would undergo its revolution just a few years prior, that did little to give a voice to the rural poor and working-class in the country.

Democratic elections did abate some of the unrest, but a US-backed coup would see the installation of a military dictator Carlos Castillo Armas. Military cadets would start the conflict, but regular participants would change with the ebb and flow of the war itself.

Guatemala is still reeling from the aftereffects of the war. With around 200,000 dead or wounded, it is one of the bloodiest conflicts waged in the latter half of the 20th century. In its wake, it would see the reinstatement of democratic elections and civilian rule.

Thirty-Eight Years’ War

A painting of the Emishi paying homage to Prince Shotoku
The Thirty-Eight Years’ War was a conflict waged in Ancient Japan by the Japanese Army and the Emishi.

One of the major participants of the Thirty-Eight Years’ War was the Emishi, an ethnic group who lived in Ancient Japan. Like many wars of the Medieval era, the Thirty-Eight Years’ War served as a massive power struggle.

The Emishi were fighting a losing battle from the start of the war in 773, despite massive victories against Japanese forces. The core battles of the war were over by 802 due to another group of Emishi allying with the newly appointed Shogunate of Japan. However, local fighting was still taking place through 811.

Chicimeca War

the longest wars in history
The Chichimeca War would see massive changes for New Spain in its aftermath.

Spain’s establishment of colonies in North and South America is a history written in blood and conflict. The Chicimeca War is the longest of these conflicts and would prove instrumental in establishing a foothold for the Spanish empire. The full weight of the Spanish empire would be pitted against the Chicimeca Confederation, a loose alliance of semi-nomadic indigenous people.

The war began in 1550 and would primarily be waged in various states of modern-day Mexico, serving as an extension of an earlier armed rebellion. While Spain was fully capable of waging one of the longest wars in history, no nation could bankroll such a conflict forever.

The Spanish treasury would find itself nearly fully depleted by 1574, although the conflict did not end until 1590. However, after 1574, the war would move to a new phase, with the Spanish empire more readily integrating the Chichimeca into the empire. The final strategy would pay off, and a large swath of land became part of New Spain.

Kongo Civil War

Kongo Civil War
Many different factions were vying for territory and control during the Kongo Civil War.

With a duration of 44 years, the Kongo Civil War is one of the longest wars in history. It is also the first in our list to be found on the African continent. The actual source of the conflict is one of succession, as you’ll find time and time again with empires and kingdoms. The Kingdom of Kongo was at its absolute height during the reign of King Garcia II.

1661 would see King Garcia II’s passing, and his second eldest son Antonio I would take the throne. The war began in earnest at the small border town of Mbwila, sparked off by growing tensions with the Dutch in Angola.

The war itself, while being one of the longest in history. It is more notable for being a series of succession crises marked by political intrigue from the Soyo, Kimpanzu, and Kinlaza factions found in the kingdom.

Kongo’s civil war would draw to a close in 1709, although some sources put this as late as 1718, marking at least 44 years of conflict. It would see numerous kings come and go before King Pedro IV took the throne. Pedro IV would be instrumental in reunifying the kingdom and stamping out the remaining fires and pockets of resistance found throughout the nation.

Dutch-Portuguese War

longest wars in history
Most major battles of the Dutch-Portuguese War would be waged with naval power over infantry.

You might have thought you’d see the last of the Dutch, but this wide-ranging conflict saw the Dutch Republic waging a massive naval war against the Portuguese. The Iberian Union was one of the eminent powers of Europe. Spain and Portugal’s naval dominance was something to behold.

That would be challenged in 1602 by both the Dutch East India Company and Dutch West India Company before the full power of the Dutch government would come into the conflict. While wars in Europe weren’t uncommon, especially in the 16th and 17th centuries, this one was different in overall scope.

It is primarily a naval conflict, with most of the theaters of war being on oceans and straits. The conflict would officially end in 1661, with a Treaty of Truce signed in the Hague being its resolution.

Sixty Years’ War

Sixty Years' War
The Sixty Years’ War would see the Kingdom of England cede massive territories in North America.

This long-ranging war serves as more of an umbrella to look over the conflict between French and British interests in the North American continent. You’ll find some of the major formative events for the United States here, with the French-Indian War, American Revolution, and War of 1812 all serving as essentially major stages of this massive conflict.

The war itself would last from 1754 to 1815, with the War of 1812 being the last of the official hostilities conducted by British forces against French allies. This is where the United States would be formed, the Declaration of Independence signed, and ultimately when the capital of the fledgling nation would be torched.

While the greater framework for the Sixty Years’ War frames flashpoints in conflict, it has a larger purpose. The war would see the United States expand greatly, and valuable territories like the Great Lakes would be integrated into the new nation-state.

Darfur Civil War

Longest wars in history
The Darfur Civil War was ignited by a succession crisis.

The Sultanate of Darfur once resided in what is now modern Sudan. Not much can be said about the conflict itself, as there isn’t a wealth of English primary sources. However, the conflict itself came about as a result of a succession crisis. The once powerful Ahmed Bukr’s death in 1722 would catalyze the conflict itself.

A massive civil war sparked off as a result of disputes between Bukr’s sons, with each potential heir wanting a piece of the kingdom. While the dispute would eventually be settled in 1786 after 64 years of constant conflict, it had a larger effect on the kingdom.

The Sultanate of Darfur would decline, and would further engage in conflicts with Sennar and Wadai. What once was one of the most powerful kingdoms in Africa would eventually become an imperial possession in the centuries to come.

French Conquest of Algeria

The French Conquest of Algeria
France’s annexation of Algiers was one with quite a heavy cost in manpower on both sides.

The French Conquest of Algeria is another tale of imperialism. It was at a far higher cost of life than previous means of expansion. Algiers would be invaded in 1830, which would spark a war lasting almost 73 years. While this is among the longest wars in history, it is one drenched in blood.

Algeria would account for an estimated 500,000 to 1 million casualties. The French aggressors would pay their share of casualties as well. French casualties accounted for around 200,000 military losses by the end of the conflict.

This had longer-reaching implications than most imperialist conquests of the 19th century. France would hold on to the region until 1962. Algiers would be home to another massive conflict following the Second World War. The subsequent victory would lead to complete independence from the French.

Umayyad Conquest of Hispania

ummayad conquest of hispania
While it would take some time to conquer the whole of Iberia, Muslim rule would persist for centuries in its aftermath.

The Iberian peninsula has been one of the most valuable pieces of land in Western Europe for centuries. The Umayyad Caliphate certainly agreed with the notion, sparking off one of the longest-lasting wars in history to conquer the area. This conflict directly ties into the longest war of all recorded history as well.

The resulting conflict would see Spain come under Muslim rule. This was one of the absolute longest wars in history, starting in 711 and ending in 788. The Umayyad’s conquest of the Iberian peninsula had wide-ranging implications for the entire region.

Most of Europe was staunchly Christian, and the threat of Muslim rule on the continent would spark the longest war in all of history.

The Muslim Conquest of Transoxiana

The Muslim Conquest of Transoxiana
Both the Abbasid and Umayyad Caliphates would establish a firm foothold in Central Asia following the Conquest of Transoxiana.

Transoxiana is a region of Central Asia that includes parts of Uzbekistan, Tajikistan, Kazakhstan, and Kyrgyzstan. The region would ignite a long-spanning war lasting 78 years. The Muslim conquest of the region was spearheaded by the Umayyad and Abbasid Caliphates.

Large tracts of land were conquered fairly swiftly from 705 to 715. However, that entire region wouldn’t be entirely pacified until 751. Incursions into the region by both the Umayyad and Abbasid militaries would begin in 673.

The end would result in over 200 years of rule, until the liberation of Bukhara in 999. This marked the end of Abbasid’s influence and started the prominence of Turkish forces in the area.

Eighty Years’ War

Eighty Years' War
The Eighty Year’s War was a costly and bloody conflict with no conclusive victor.

This guide won’t be enough to do justice to the Eighty Years’ War. The Eighty Years’ War was another conflict centered around the Dutch and the Spanish. It finds its origins in 1568, with many disputed causes including maritime trade, taxes, and religious differences.

The Eighty Years’ War would last until 1648 and involved allies like England, France, Anjou, Portugal, and the Holy Roman Empire. There was no conclusive victor despite the nearly 100 years of bloodshed. All participating kingdoms would be saddled with enormous war debt and discontented populations.

The Peace of Munster would draw the war to a close, with countless dead and wounded in its wake. This would also formally recognize the northern, Protestant-dominated part of the Netherlands as the Dutch Republic.

Anglo-Afghan War

Anglo-Afghan War
The conclusion of the Afghan War coincided with the aftermath of The Great War.

Some of the longest wars in history are waged under the guise of imperial expansion. The Anglo-Afghan War was a long-spanning conflict, running from 1839 to 1919. It boggles the mind to think that The Great War was being fought simultaneously while the British Empire continued trying to subjugate Afghanistan.

Despite massive losses in Afghanistan, the war would prove to be an Afghani victory. Following the cessation of hostilities in 1919, the United Kingdom would officially recognize Afghanistan’s sovereignty. The Durand Line would be established in the aftermath, demarcating the border between India and Afghanistan.

Russo-Circassian War

Russo-Circassian War
After a lengthy way, Russian forces would conduct a mass expulsion and genocide of the remaining Circassian population.

Not much focus is given to Russian conflicts when looking through our Western lenses. However, the sphere of influence and power exerted by the Russian Empire cannot be understated. The Russo-Circassian War marks one of the longest wars in history, lasting well over a century of constant conflict.

The war itself started in 1763 and concluded in 1864, knocking right on the heels of the American Civil War. Circassia was a region in the Caucasus and one of the fiercest fights given to the Russian Empire.

Sadly, this war ended in a complete Circassian defeat, followed by mass expulsion and genocide for the affected ethnic groups inhabiting the area.

The Hundred Years’ War

The Hundred Years' War
The Hundred Years’ War was primarily conducted by the Kingdoms of England and France.

If you’ve cracked open a World History book, you’ve likely seen the Hundred Years’ War in passing. It refers to an umbrella for a series of different conflicts in the late Middle Ages. However, the main combatants throughout this 116-year war were England and France.

The original cause of the war boils down to succession and claims to the throne. England was a solidified power at this point, but the kings of England believed themselves to be the successors to the French throne. This is a rather unusual conflict, with numerous starts and stops throughout.

Starting in 1337 and officially concluding in 1453, the Hundred Years’ War would result in a French victory. England’s continental lands on the European mainland would be ceded, and the financial turmoil led to great civil unrest.

The Second Hundred Years’ War

The Second Hundred Years' War
The Second Hundred Years’ War was a massive war encompassing some of Western history’s biggest events.

France and England’s centuries-old bad blood isn’t over just yet. The Second Hundred Year’s War is a blanket term used for historical classification purposes. However, when looking at the key belligerents and the dates of the conflicts, you could readily classify this as one of the longest wars in history.

The Second Hundred Years’ War started in 1689 and lasted until around 1815. This includes some massive historical events, like the American and French Revolutions. You’ll also see Britain and France squaring off over succession in wars like the Spanish and Austrian conflicts.

Interestingly, this would mark the last of the protracted conflicts between England and France. This came after almost 1000 years of warfare and political intrigue between the neighboring kingdoms.

Sengoku Period

Sengoku Period
The Sengoku Period was one of constant strife with the result being a unified Japan.

Starting in 1467, the Sengoku Period was one of utter chaos and constant civil war in Feudal Japan. Long before the country was unified under a single banner, it was ruled over by daimyo, or warlords. The Sengoku Period saw constant upheaval, bloodshed, and ever-changing territories.

The conflict would rage for almost 150 years, ending finally in 1615. With the rise of Tokugawa Ieyasu as the shogun, Japan would be unified for the first time in years. In its wake, this period of warfare left countless casualties and allowed for a fair bit of European influence through Dutch and Portuguese merchants trading weapons and goods to various factions.

The Crusades

The Crusades
While they were primarily waged as holy wars, The Crusades drew in most of the major powers of Europe.

The Crusades aren’t any single war, necessarily, but the overall aim is the same. With open conflict lasting from 1096 to 1291, it is one of the longest wars in history. The almost 200-year-long conflict was directed primarily by the Vatican.

The scope of each of the eight Crusades varied, with aims like reclaiming the Kingdom of Jerusalem, continued defense of the area, and curtailing the expansion of the Ottoman Empire. I don’t have enough space to summarize the whole of the Crusades, but it had a significant impact on the whole of Europe and the Middle East.

Roman Conquest of the Iberian Peninsula

The Roman Conquest of Iberia
While Rome’s conquest of Iberia took well over a century, it resulted in massive territory gains for the Roman Empire.

One of the longest wars in recorded history hails from the Roman Republic. This takes place well before any of the previously mentioned conflicts, lasting from 218 BCE to 19 CE. Rome would exist as a republic, waging war against the Carthaginians during this period.

The conflict would finally end with the complete annexation of the Iberian peninsula, something that was solidified by the first emperor Augustus. While Rome’s reign over the region would continue until the decline of the Western Roman Empire, it would influence the politics of the area for centuries to come.


When the Ummayad Conquest of Hispania ended, the Reconquista began.

This is the absolute longest war in history. The Reconquista is a direct consequence of the Ummayad Conquest of Hispania. If you thought Muslim forces conquering Spain ruffled some feathers in Europe, you would be correct.

The Reconquista started in 718 and ended in 1492, lasting for 774 years. It essentially started with the conclusion of the Ummayad conquering the region and lasted for the better part of 1000 years.

A series of invasions, military campaigns, and Church-ordered actions would lead to Spain becoming a Christian kingdom once again in 1492.

The 21 Longest Wars in History Summary

RankWarYears Fought
21The Aceh War1873-1904
20Ayutthaya-Lan Na War1441-1474
19Guatemalan Civil War1960-1996
18The Thirty-Eight Years’ War773-811
17The Chicimeca War1550-1590
16The Kongo Civil War1665–1709
15The Dutch-Portuguese War1602-1661
14The Sixty Years’ War1754-1815
13Darfur Civil War1722-1786
12French Conquest of Algeria1830-1903
11Umayyad Conquest of Hispania711-788
10The Muslim Conquest of Transoxiana673-751
9The Eighty Years’ War1568-1648
8The Anglo-Afghan War1839-1919
7The Russo-Circassian War1763-1864
6The Hundred Years’ War1337-1453
5The Second Hundred Years’ War1689-1815
4The Sengoku Period1467-1615
3The Crusades1096-1291
2The Roman Conquest of the Iberian Peninsula218 BCE-19 CE
1The Reconquista718-1492

Frequently Asked Questions

What is the longest war in history?

The Reconquista of Spain is the one recognized as having the longest duration. The conflict itself lasted 774 years.

Did Britain and France have any additional wars following the Second Hundred Years' War?

No, France engaged in hostilities elsewhere, but both European powers would end up as allies when the First World War came around.

Do any of these wars take place in the modern day?

The Guatemalan Civil War concluded in the 1990s and is one of the most recent of the long-runners to conclude.

Are there good primary sources for these conflicts?

Yes, all of the conflicts are well-documented by academic sources. For example, you can locate more information on the Crusades at the University of London’s website.

Are there any long-ranging conflicts still happening?

Yes, some like the Kurdish rebellions in Turkey and the Rohingya Insurgency are still being waged right now.

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