On this day a battle took place, one which is according to many historians one of the most decisive and fateful in history. Namely, that battle may well have saved Europe from being conquered by the Muslims. The battle is usually called the Battle of Poitiers, but actually took place somewhat farther away, roughly at the location of what is now the village of Moussais-la-Bataille in the heart of France.
The battle is notable because it was the turning point which stopped the Muslim invasion of Europe. Namely, Islam had spread rapidly since the time of the Prophet Muhammad (around 622). The Muslims conquered the whole of North Africa. In 711, Muslim leader Tariq ibn Ziyad invaded Spain (in fact, Gibraltar was named after him, derived from the Arabian term Gebel-al-Tārık). Soon they conquered the whole of Spain, and France was next in line.
The Muslim advance launched on this day had the goal to plundering the famous Basilica of St. Martin in Tours (St. Martin was once the Bishop of Tours). At that time, France was ruled by kings from the Merovingian dynasty, but the real power was held by their majordomos from the Carolingian family. The leader of the Christian defenders of Tours was precisely Majordomo Charles from the Carolingian family.
The battle was one by the Christians. The victorious majordomo Charles received the nickname Martel (“The Hammer”). Even the Muslim commander Abdul Rahman al Gafiki died in the battle (he was of Arab descent). The defeated Muslims withdrew to southern France, where they held out for a while, but were eventually pushed back across the Pyrenees and into Spain. They never managed to penetrate so far into Europe again.