The Battle of Tours was important because it stopped the growth of Islam. If the Muslims had won that battle, Christianity might not be anything like it is today, because Western Europe was a major site of Christianity. Although Islam had been spreading with Muslim conquest, their victories had ceased around 715 A.D.. The Muslims failed in trying to siege Constantinople from 717-718 A.D., and the Muslims had been forced out of Iran by Turkish forces. The Battle of Tours, 732 A.D., was another loss of the Muslims. Charles Martel defeated them, and fought many other battles with them, which earned him the title “Hammer,” or Martel.
I think the Battle of Tours affected our world history dramatically, because if the Battle of Tours had not been won by Charles Martel, the state of Christianity would probably be very different.