The Battle of Tours, known as Balat aix-Xuhadà (The Highway of the Martyrs) in Arabic, took place on October 10th 732 between the Frankish forces under Charles Martel and the Islamic army led by Emir Abd-ar-Rahman ibn Abd-Al·lah al-Ghafiqí betwen the towns of Tours and Poitiers in France.
The Franks won a resounding victory, Al-Ghafiqí was killed in the battle and so the Muslim invasion of Europe was halted and the continent remained Christian at a time when when the Byzantine and Persian Empires were falling to Islam.
It is difficult to be certain of the size of the armies but historians suggest that the Franks numbered between 15,000 and 75,000 men whilst the Muslim force numbered between 60,000 and 400,000 men so it was one of the major battles in European history up to that point.
The victory led to the creation of a buffer zone between the Frankish Kingdom and the Muslim Al- Andalus, known as the Marca Hispanica or Spanish March, which would ultimately develop into Catalonia.
The Muslims in the north of the Iberian Peninsula had conquered Septimania easily and had occupied its capital Narbonne, which they renamed Arbuna and from where they ruled the region they called the Waliate of Arbuna.
Odo the Great of Aquitania had defeated an important Muslim invasion force at the Battle of Toulouse in 712 but despite this, the raids continued and the Muslims managed to take the city of Autun in Burgundy in 725.
Threatened by the Arabs to the south and the Franks to the north, Odo the Great reached an agreement with Uthman ibn Naissa, the first Wali of Arbuna, in which he gave his daughter Lampade in marriage and the raids stopped.
The following year Uthman ibn Naissa led a revolt against the Governor of Al Andalus, Abd-ar-Rahman al-Ghafiqí, which was put down easily and Abd-ar-Rahman al-Ghafiqí turned his attention against Odo the Great and Aquitania.
Odo gathered his forces at Bordeaux and after being defeated at the Battle of the River Garonne, he called for help from the Franks, whose leader agreed as long as Odo submitted to Frankish authority.
In 732, a Muslim force started making its way up the Loire Valley possibly with the aim of capturing the treasure housed in the Abbey of Saint Martin of Tours.
On hearing this Charles, the Mayor of the Palace of Austrasia, put together an army of somewhere between 15,000 and 75,000 men and went to meet the Muslim force.
According to Arabic sources, Charles Martel placed his troops, made up mainly of infantry armed with swords, lances and shields, in a defensive position somewhere close to Tours, the precise location of which is not known, and waited for the Muslim army to advance.
The Muslims were greater in numbers and comprised mainly armed cavalry wearing armour and so should have had the advantage but, given that he had chosen the location, Charles Martel was able to fight a brilliant defensive battle.
For six days, the two armies watched each other, engaging only in minor skirmishes, neither wanting to attack first.
The battle finally came on the seventh day because Abd-ar-Rahman al-Ghafiqí didn't want to wait any longer because his men weren't as well prepared for the cold weather as the Franks.
The Muslims, confident in their superiority attacked, but on one of the rare occasions medieval infantry got the better of cavalry, the Franks held their position and fought off the attacks.
According to Arabic sources, late in the day or perhaps on the following one, a rumour went round the Muslim force that the Frankish cavalry had left to capture their booty that had been left in Bordeaux and many returned to camp.
As he tried to stop the retreat, Abd-ar-Rahman al-Ghafiqí was surrounded by Franks and killed and, having lost their leader, the Muslim army pulled back completely finally taking a position much further south.
As a result of the battle Charles earned the name Martel or Hammer and he would continue to push the Muslims out of Aquitania and Septimania over the coming years, achieving important victories at the Battle of the River Berre and the Siege of Narbonne both in 737.
The historical views of this battle fall into three great phases, both in the East and especially in the West.
Western historians, beginning with the Mozarabic Chronicle of 754, stressed the macro-historical impact of the battle, as did the Continuations of Fredegar both of which stressed that Charles Martel had saved Christianity.
Edward Gibbon and his generation of 18th historians agreed that the Battle of Tours was unquestionably decisive in world history and there is also a large number of modern historians who follow the same line of thought.
However, there is another modern view which argues that the Battle has been massively overstated and turned from a raid into an invasion, from a mere annoyance to the Caliph to a shattering defeat that helped end the Islamic Expansion Era.
A number of historians agree that the Battle was of macrohistorical importance but take a more moderate and nuanced view of its significance, in contrast to the more dramatic and rhetorical approach of Gibbon.
The best example of this school is William E. Watson, who while accepting the importance of the Battle, but analyses it militarily, culturally and politically, rather than seeing it as a classic "Muslim versus Christian" confrontation.
In the East, Arab histories followed a similar path, initially regarding the battle as a disastrous defeat.
It then largely faded from Arab histories, leading to a modern dispute which regards it as either a secondary loss to the great defeat of the Second Siege of Constantinople, where the Bulgarian Emperor Tervel played a crucial role, or a part of a series of great macrohistorical defeats which together brought about the fall of the first Caliphate.
With the Byzantines and Bulgarians together with the Franks both successfully blocking further expansion, internal social troubles came to a head, starting with the Great Berber Revolt of 740, and ending with the Battle of the Zab.
This led to the destruction of the Umayyad Caliphate and the end of Islam's first period of great expansion.