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The Reconquista -

The Reconquista was all about Christians conquering territory from Muslims in the Iberian Peninsula (Spain and Portugal). Its beginnings were marked by the victory of Don Pelayo of Asturias at Covadonga around 720 CE.

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The Reconquista -

This series of wars lasted for 780 years, and it's estimated that around seven million people died as a result.

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The First Crusade -

The First Crusade was declared in 1095. The idea was to seize Jerusalem from Islamic rule. Though this was just the beginning of the Roman Catholic Church's campaign, and it eventually turned into a 300-year-long bloodbath.

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The Crusades -

More Crusades followed, and while it's difficult to calculate the number of deaths during the First Crusade, in total it is estimated that about 1.7 million lives were lost during the whole period of the Crusades.

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The Crusades -

While mostly Muslims and Christians died during this period, Jewish people also fell victims of the Crusaders.

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The French Wars of Religion -

The French Wars of Religion took place in the 16th century. The country was pretty much divided between Catholics and Huguenots (Protestants).

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The French Wars of Religion -

Perhaps the most infamous event of the time was the St. Bartholomew's Day Massacre of 1572, where a mob of Catholics attacked Huguenots.

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The French Wars of Religion -

The wars ended when Huguenot Henry III of Navarre became King Henry IV of France and converted to Catholicism.

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The French Wars of Religion -

In 1598, the 'Edict of Nantes' was issued, granting religious freedom and rights to Huguenots, marking the end of the 36-year-long conflict.

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The Thirty Years' War -

This European war took place in the Holy Roman Empire and lasted from 1618 to 1648. It started as a Catholics versus Protestants conflict in Prague, and it escalated from there.

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The Thirty Years' War -

It's regarded as one of the most devastating wars in European history, with an estimated eight million lives lost. But there were more causalities than just battlefield deaths.

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The Thirty Years' War -

The war happened during a cold snap in Europe, meaning that low temperatures affected agriculture, leading to food shortages and consequently famine and more deaths.

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The Circassian War -

This conflict took place when Orthodox Russia  expanded towards the Black Sea in the 18th century, clashing with the Islamic Ottoman Empire.

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The Circassian War -

The Russians faced resistance from the peoples of the North Caucasus. The Muslim Caucasian mountaineers fought off the Orthodox Russians between 1763 and 1864.

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The Circassian War -

When the Russians' military strategy failed, they evicted the Caucasians from their homelands. In 1864, almost three million Muslim Adyghe, Ubykhs, and Abkhaz were sent to the Ottoman Empire on ships. Many of those sank.

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The French Revolution -

There was a strong anti-Catholic sentiment during the French Revolution. The whole dechristianization of the country was among the goals of the revolutionaries.

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The French Revolution -

One of the laws imposed by the revolutionaries was the Civil Constitution of the Clergy, where all Catholic clergy had to swear loyalty to the state.

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The French Revolution -

But not ever French person was in favor of the revolution, and many fought back. It is estimated that French forces massacred over 50,000 people during the Reign of Terror alone.

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The Taiping Rebellion -

This war against the Manchu imperial dynasty began in 1850 and lasted 14 years. It was instigated by a Chinese revolutionary named Hong Xiuquan.

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The Taiping Rebellion -

While the dispute was mostly territorial, Hong Xiuquan claimed to be Jesus Christ's younger brother, whose mission it was to fight the Confucian demons, i.e. the Manchu empire.

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The Taiping Rebellion -

Xiuquan establish the Heavenly Kingdom of Great Harmony (Taiping Tianguo), but his rebellion was eventually defeated. It is estimated that around 20 million people died during the conflict.

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The Bolshevik Revolution -

The Bolshevik Revolution was instigated by socialists (later communists) against tsarists. The socialists/communists were militant atheists, and as such sought to eliminate all religion, most notably the Russian Orthodox Church.

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The Bolshevik Revolution -

Though religion was never banned, the USSR later targeted religious communities who were connected to the tsarist regime. It is estimated that around 30 million died in the Bolshevik Great Terror of 1936–1938.

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The Ottoman Christian genocide -

The Armenian Genocide by the Ottoman Empire took place in 1915 and resulted in the slaughter of thousands of Armenian people and their identity.

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The Ottoman Christian genocide -

But the Armenian Genocide was just one event in the Ottoman Empire's persecution of Christian communities between 1914 and 1923. It started in 1914 with the massacre of Assyrian Christian communities, followed by the Armenians. By 1918, over 600,000 Assyrians and 1.5 million Armenians had died.

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The partition of India -

The partition of India took place in 1947 and divided British India into the modern states of India and Pakistan.

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The partition of India -

Violence between Hindu, Muslim, and Sikh groups followed. The conflict was paired with mass migration.

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The partition of India -

It's estimated that around two million people were killed, and at least 15 million were displaced.

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The Second Sudanese Civil War -

South Sudan was born in 2011, out of a bloody conflict between the Christian and animist south and the Muslim north.

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The Second Sudanese Civil War -

It is estimated that at least two million lives were lost to the conflict, and hundreds of thousands of people were displaced.

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The Syrian civil war -

The Syrian civil war began in 2011, following the Arab Spring of 2010. Syrian president Bashar Assad's opposition was composed of (among others) radical Islamists, including ISIS.

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The Syrian civil war -

The war spread to Iraq, where ISIS targeted minority groups, namely Yazidis and Assyrian Christians. Shia Muslim Turkmen were also killed.

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The Syrian civil war -

It is estimated that around 5,000 Yazidis were killed, 400,000 were displaced, and 6,000 enslaved.

Sources: (Grunge) 

See also: What does the Bible say about war?

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