Military victories
For early medieval authors, Charles was famous for his military victories. Paul the Deacon for instance attributes a victory against the Saracens actually won by Odo of Aquitaine to Charles. However, alongside this there soon developed a darker reputation, for his alleged abuse of church property. A 9th-century text, the Visio Eucherii, possibly written by Hincmar of Reims, portrayed Charles as suffering in hell for this reason. According to Fouracre, this was "the single most important text in the construction of Charles's reputation as a seculariser or despoiler of church lands".
By the 18th century, historians such as Edward Gibbon had begun to portray the Frankish leader as the saviour of Christian Europe from a full-scale Islamic invasion. 19th century German historian Heinrich Brunner argues that Charles had confiscated church lands in order to fund military reforms that allowed him to defeat the Arab conquests, in this way brilliantly combining two traditions about the ruler. However, Fouracre argues "...there is not enough evidence to show that there was a decisive change either in the way in which the Franks fought, or in the way in which they organised the resources needed to support their warriors." Many 20th-century European historians continued to develop Gibbon's perspectives, such as French medievalist Christian Pfister, who wrote in 1911:
"Besides establishing a certain unity in Gaul, Charles saved it from a great peril. In 711 the Arabs had conquered Spain. In 720 they crossed the Pyrenees, seized Narbonensis, a dependency of the kingdom of the Visigoths, and advanced on Gaul. By his able policy Odo succeeded in arresting their progress for some years; but a new vali, Abdur Rahman, a member of an extremely fanatical sect, resumed the attack, reached Poitiers, and advanced on Tours, the holy town of Gaul. In October 732—just 100 years after the death of Mahomet—Charles gained a brilliant victory over Abdur Rahman, who was called back to Africa by revolts of the Berbers and had to give up the struggle. ...After his victory, Charles took the offensive".
Similarly, William E. Watson, who wrote of the battle's importance in Frankish and world history in 1993, suggests:
"Had Charles Martel suffered at Tours-Poitiers the fate of King Roderick at the Rio Barbate, it is doubtful that a 'do-nothing' sovereign of the Merovingian realm could have later succeeded where his talented major domus had failed. Indeed, as Charles was the progenitor of the Carolingian line of Frankish rulers and grandfather of Charlemagne, one can even say with a degree of certainty that the subsequent history of the West would have proceeded along vastly different currents had 'Abd al-Rahman been victorious at Tours-Poitiers in 732."
Political scientist Samuel Huntington sees the Battle of Tours as marking the end of the "Arab and Moorish surge west and north". Other recent historians, however, argue that the importance of the battle is dramatically overstated, both for European history in general and for Charles's reign in particular. This view is typified by Alessandro Barbero, who writes:
"Today, historians tend to play down the significance of the battle of Poitiers, pointing out that the purpose of the Arab force defeated by Charles Martel was not to conquer the Frankish kingdom, but simply to pillage the wealthy monastery of St-Martin of Tours".
Similarly, Tomaž Mastnak writes:
"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... One of Fredegar's continuators presented the battle of Poitiers as what it really was: an episode in the struggle between Christian princes as the Carolingians strove to bring Aquitaine under their rule."
More recently, the memory of Charles has been appropriated by far right and white nationalist groups, such as the 'Charles Martel Group' in France and by the perpetrator of the Christchurch mosque shootings at Al Noor Mosque and Linwood Islamic Centre in Christchurch, New Zealand, in 2019. The memory of Charles is a topic of debate in contemporary French politics on both the right and the left.
In the 17th century a legend emerged that Charles had formed the first regular order of knights in France. In 1620, Andre Favyn stated (without providing a source) that among the spoils Charles's forces captured after the Battle of Tours were many genets (raised for their fur) and several of their pelts. Charles gave these furs to leaders amongst his army, forming the first order of knighthood, the Order of the Genet. Favyn's claim was then repeated and elaborated in later works in English, for instance by Elias Ashmole in 1672 and James Coats in 1725.