7 longest wars in world history that lasted over 100 years

The prolonged war between England and France marks a significant place in the history of the world. It is not only known for its iconic battles and political rift, but also as a key chapter in the larger Anglo-French conflicts that stretched from 1066 to 1776.

The Hundred Years' War, which spanned from 1337 to 1453, holds a unique place in history as a prolonged conflict between two European powers—England and France. It consisted of intermittent battles sparked by competing claims to the French crown and disputes over territorial control in France.

Over the centuries, numerous other wars across the world have also significantly influenced the formation of national borders and identities. These historic conflicts, often fuelled by political goals, ideological differences, and cultural loyalties, which played a decisive role in steering the direction of human history.

1. Iberian religious war

It is marked as the longest continuous war in human history, fought between the Catholic Spanish Empire and the Moors living in what is now Morocco and Algeria. The conflict, commonly known as the Reconquista, lasted for nearly 781 years.

This is also considered the earliest religious war that took place outside the Arab world. The conflict began in 711 CE and came to an end in 1492 CE with claiming nearly 7 million lives. The war started after the Moors claimed territory in Europe, prompting the Spanish Empire to launch an attack against the Moors as viewing them as a threat.

2. Persian-Roman wars

Another longest-standing rivalries unfolded between the Roman Empire and the Persian powers, first the Parthians and later the Sassanids. This prolonged conflicts revolved around control of frontier cities and territories along their shared borders.

The conflict, which ran from 92 BC to 629 AD, lasted nearly 720 years, resulting in substantial economic damage and weakening both empires, making them more susceptible to external invasions.

3. Roman-Germanic war

This war began on 113 BC and lasted till 596 CE, spanning over 708 years of long history between the Roman Empire and various Germanic tribes. The conflict was evident as the Roman-Germanic Wars played a vital role in shaping the course of European history. The confrontations were driven by a combination of territorial disputes, cultural clashes, and the expansionist ambitions of Rome.

4. Arauco war

It spanned nearly three centuries (1536–1825 CE) and was fought between Spanish colonial forces and the native Araucanian tribes, later forming Chile, primarily the Mapuche, Picunche, and Huilliche. At the time, Spain had gained control over much of South America and aimed to suppress indigenous resistance, which benefited from both terrain and resilience.

The conflict finally ended in 1825 after diplomatic negotiations between Spain and Chile that aligned with Chile's struggle for independence.

5. Byzantine–Seljuq wars

Over 300 years (1048–1348 CE), the Byzantine Empire was locked in an enduring struggle with the Seljuk Turks. These clashes focused on dominance over Asia Minor and neighbouring territories, parts of which now lie in modern-day Europe.

Though the Seljuks lost some ground during the Crusades, the repeated confrontations overextended the Byzantine military and economic resources. This sustained warfare greatly contributed to the empire's eventual weakening and decline.

6. Polish–Russian wars

From 1577 to 1794, Poland and Russia were entangled in a long series of wars that lasted 217 years, deeply shaping the political landscape of Eastern Europe. These conflicts stemmed from the intense rivalry between the Polish-Lithuanian Commonwealth and the Russian Tsardom, involving competition for control over Ukraine, Belarus, and the Baltic region. Motivated by territorial, dynastic, and religious disputes, the wars dramatically shifted the regional balance of power.

7. Ottoman–Byzantine wars

The protracted struggle between the Byzantine Empire and the rising Ottoman Turks lasted roughly 215 years from the 13th to the 15th centuries.
As the Ottomans expanded steadily, the Byzantines lost much of their territory. The defining moment came with the 1453 conquest of Constantinople by Sultan Mehmed II, marking not only the end of the Byzantine Empire but also signalling the close of the European Middle Ages.