1. Battle Of Tours (732)
The collapse of the Roman Empire ushered in a new period in mainland Europe. For the first time since the 2nd and 3rd centuries BC, Gaul was free from Roman rule. The Franks, a Germanic tribe who emerged from the Netherlands/Belgium region, settled in northern France and Clovis I, a member of the Merovingian dynasty, conquered most of Gaul towards the end of the 5th century. Europe was fractured around this time, with different tribes controlling different regions, and it was around this time that Christianity started to become the major religion it was often used to unite tribes under one cause. Islam had been attempting to breach Europe on both the east and west sides. On the eastern front the Arabs, under the leadership of Khalid ibn al-Walid, massacred the Byzantine army at Yarmuk, driving them out of Syria. They attempted the first siege of Constantinople, but, with the help of 'Greek Fire', the Arabs were held back. After conquering most of northern Africa, and thus creating an empire larger than that of the Romans, the Umayyad Caliphate crossed over to the Iberian Peninsula. At Guadalete, in 711, the Arab and Berber forces, under the command of Teriq ibn Ziyad, crushed the Christian Visigoths. The Muslim forces took Spain and headed up into southern Gaul, taking Aquitaine and Bordeaux. Odo of Aquitaine, despite losing much of his land, hated the Franks and attempted to form an alliance with the Moors. Unfortunately, a civil war in Muslim Iberia resulted in Abdul al-Rahman becoming the emir of Cordoba. Al-Rahman continued the conquest, forcing Odo to seek an alliance with Charles Martel, Mayor of the Palace in the Merovingian Frankish kingdom. Just north of Poitiers, al-Rahman's force, preparing to loot Tours, came into contact with the Frankish army. Martel had positioned his forces on a hill, blocking a direct route to the town. A forest surrounded them, hiding the true size of his force and making it tougher for the Muslim cavalry to attack as one. He hoped al-Rahman would attack directly, hoping to reach Tours. The Moorish commander did so, but the cavalry charges failed to breach the tight, defensive lines. The key point in the battle came when rumours began circulating that the Franks had snuck into the Muslim camp and were stealing loot taken from Bordeaux. The cavalry headed back to the camp, and al-Rahman soon found his army in chaos. The Franks attacked and al-Rahman was killed. Charles Martel became a heroic figure of Christian Europe and his grandson, Charlemagne, was crowned an emperor by the Pope. It began the unification of Europe as a Christian continent and saw some of the borders we know today being formed. If the Moors had won, it's almost certain Islam would have spread through mainland Europe if they had wanted it. The most desirable areas of Europe were held by the Byzantine Empire, which could have led to an epic clash between the two forces. The rest of mainland Europe was a bit of a backwater. If they had taken it, Europe would have been divided into separate Islamic states rather than one big one and Christianity may have suffered the same fate as the Pagan religions which preceded it. If that would have happened, it's almost certain it would have spread to the 'New World', the same that Christianity did after the Europeans arrived in the Renaissance age.