During most of his tenure in office as commander-in-chief of the Franks, the Frankish kingdom consisted of north and eastern France (Austrasia, Neustria and Burgundy), most of western Germany, and the Low Countries (Luxembourg, Belgium and the Netherlands).

However, it continued to struggle against external forces such as the Saxons, Frisians, and other opponents such as the Basque-Aquitanians led by Odo the Great (Old French: Eudes, or Eudo), Duke of Aquitaine and Vasconia.

This defeat did not stop incursions into old Roman Gaul, as Moorish forces, soundly based in Narbonne and easily resupplied by sea, struck eastwards in the 720s, penetrating as far as Autun in Burgundy in 725.

[28] The chronicle added that they "pierced through the mountains, trampled over rough and level ground, plundered far into the country of the Franks, and smote all with the sword, insomuch that when Eudo came to battle with them at the River Garonne, he fled."

As Herman of Carinthia wrote in one of his translations of a history of al-Andalus, Odo managed a highly successful encircling envelopment which took the attackers completely by surprise, resulting in the slaughter of the Muslim forces.

[29] Upon hearing this, Austrasia's Mayor of the Palace, Charles Martel, prepared his army and marched south, avoiding the old Roman roads, hoping to take the Muslims by surprise.

[33] It is thought that Bede's Ecclesiastical History of the English People (Book V, Chapter XXIV) includes a reference to the Battle of Tours: "... a dreadful plague of Saracens ravaged France with miserable slaughter, but they not long after in that country received the punishment due to their wickedness".

But Sir Edward Creasy noted that, When we remember that Charles had no standing army, and the independent spirit of the Frank warriors who followed his standard, it seems most probable that it was not in his power to adopt the cautious policy of watching the invaders, and wearing out their strength by delay.

Hallam perhaps said it best: "It may justly be reckoned among those few battles of which a contrary event would have essentially varied the drama of the world in all its subsequent scenes: with Marathon, Arbela, the Metaurus, Châlons and Leipzig.

In the last major attempt at an invasion of Gaul through Iberia, a sizable expedition was assembled at Saragossa and entered what is now French territory in 735, crossed the River Rhone, and captured and looted Arles.

The treaties reached earlier with the local population stood firm and were further consolidated in 734 when the governor of Narbonne, Yusuf ibn Abd al-Rahman al-Fihri, concluded agreements with several towns on common defense arrangements against the encroachments of Charles Martel, who had systematically brought the south to heel as he extended his domains.

[citation needed] Reluctant to tie down his army for a siege that could last years, and believing he could not afford the losses of an all-out frontal assault such as he had used at Arles, Charles was content to isolate the few remaining invaders in Narbonne and Septimania.

The first camp essentially agrees with Gibbon, and the other argues that the battle has been massively overstated – turned from a raid in force to an invasion, and from a mere annoyance to the Caliph to a shattering defeat that helped end the Islamic Expansion Era.

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, and the destruction of the Umayyad Caliphate.

The first wave of modern historians, especially scholars on Rome and the medieval period, such as Edward Gibbon, contended that had Charles fallen, the Umayyad Caliphate would have easily conquered a divided Europe.

Gibbon famously observed: A victorious line of march had been prolonged above a thousand miles from the rock of Gibraltar to the banks of the Loire; the repetition of an equal space would have carried the Saracens to the confines of Poland and the Highlands of Scotland; the Rhine is not more impassable than the Nile or Euphrates, and the Arabian fleet might have sailed without a naval combat into the mouth of the Thames.

H. G. Wells wrote: "The Moslim [sic] when they crossed the Pyrenees in 720 found this Frankish kingdom under the practical rule of Charles Martel, the Mayor of the Palace of a degenerate descendant of Clovis, and experienced the decisive defeat of [Tours-Poitiers] (732) at his hands.

"[46] Gibbon was echoed a century later by the Belgian historian Godefroid Kurth, who wrote that the Battle of Tours "must ever remain one of the great events in the history of the world, as upon its issue depended whether Christian Civilization should continue or Islam prevail throughout Europe.

Creasy quotes Leopold von Ranke's opinion that this period was one of the most important epochs in the history of the world, the commencement of the eighth century, when on the one side Mohammedanism threatened to overspread Italy and Gaul, and on the other the ancient idolatry of Saxony and Friesland once more forced its way across the Rhine.

In this peril of Christian institutions, a youthful prince of Germanic race, Karl Martell, arose as their champion, maintained them with all the energy which the necessity for self-defense calls forth, and finally extended them into new regions.

"[49] Louis Gustave and Charles Strauss said "The victory gained was decisive and final, The torrent of Arab conquest was rolled back and Europe was rescued from the threatened yoke of the Saracens.

[51]John Bagnell Bury, writing at the beginning of the 20th century, said "The Battle of Tours ... has often been represented as an event of the first magnitude for the world's history, because after this, the penetration of Islam into Europe was finally brought to a standstill.

According to Bernard Lewis, "The Arab historians, if they mention this engagement [the Battle of Tours] at all, present it as a minor skirmish,"[55] and Gustave von Grunebaum writes: "This setback may have been important from the European point of view, but for Muslims at the time, who saw no master plan imperiled thereby, it had no further significance.

The End of the Jihad State demonstrates for the first time that the cause of this collapse came not just from internal conflict, as has been claimed, but from a number of external and concurrent factors that exceeded the caliphate's capacity to respond.

These external factors began with crushing military defeats at Byzantium, Toulouse, and Tours, which led to the Berber Revolt of 740 in Iberia and Northern Africa.Ninth-century chroniclers recorded the outcome of the battle as a divine judgment in favor of Charles and gave him the nickname Martellus ("The Hammer").

Historian Norman Cantor who specialized in the medieval period, teaching and writing at Columbia and New York University said in 1993: "It may be true that the Arabs had now fully extended their resources and they would not have conquered France, but their defeat (at Tours) in 732 put a stop to their advance to the North.

Victor Davis Hanson has commented that Recent scholars have suggested [Tours-Poitiers], so poorly recorded in contemporary sources, was a mere raid and thus a construct of western mythmaking or that a Muslim victory might have been preferable to continued Frankish dominance.

Flush from the victory at Tours, Charles Martel went on to clear southern France from Islamic attackers for decades, unify the warring kingdoms into the foundations of the Carolingian Empire, and ensure ready and reliable troops from local estates.

Alessandro Barbero writes, "Today, historians tend to play down the significance of the battle of [Tours-Poitiers], pointing out that the purpose of the Muslim force defeated by Charles Martel was not to conquer the Frankish kingdom, but simply to pillage the wealthy monastery of St-Martin of Tours".

The continuators of Fredegar's chronicle, who probably wrote in the mid-eighth century, pictured the battle as just one of many military encounters between Christians and Saracens – moreover, as only one in a series of wars fought by Frankish princes for booty and territory.