This was Charles the Great of the Franks. He lived from 742 to 814 AD. His father was Pepin the Short divided his empire to Charles and his brother Carloman very shortly before his death. Carloman died soon after he began to rule over his kingdom and his son's and wife accepted Charles as king. Charles married Desiderata, the daughter of Desiderius and three years after that he divorced her and took a new wife by the name of Hildegarde. Charles later defeated the Lombards, and many other areas of what is now known as Europe. Once he did this he had formed the Roman Empire once again, which was his ultimate goal.
He was crowned Emperor by the Pope in Rome around 800 AD. During his rule there were many important things that he enforced such as travel and hospitality. He was therefore a christian king that ruled for the church, and he even gave land back to the church.
The land that he gave to the church was the Papal States. Charles the Great or Charlemange was by far one of the greatest rulers ever as he worked for the good of the church and was still capable of forming an empire and upholding this empire.