A potential model answer.

Alfred was called the Great not only because he was a brilliant military leader who defended England against Viking attack but also because he was an excellent ruler of his kingdom.

I think the most important reason why Alfred is called the Great is because he was an excellent military leader.  For example, he defeated the Vikings at the battles of Edington and Chippenham, which stopped them from taking over the whole of England. He also made an agreement with Guthrum, which meant that the Vikings were confined to the area of the Danelaw so the Saxons and their Christian religion were protected.  Furthermore he reorganised the army setting up a new system where the men of the fyrd took turns every six months looking after their farms and guarding the forts.  This meant that he always had a strong and reliable force to help keep the Vikings at bay. He also built fortifications or burhs around his towns to protect them from attack, making his country much safer to live in.  This not only meant that people could trade and work without fear, so they thought Alfred was an excellent ruler, but it also meant that they could make money to pay his taxes and help to keep him powerful.  He also revived shipbuilding, ordering ships of a new design with 60 oars to be built.  These new ships were bigger and faster than the Viking ships, which meant that England was protected from future sea attacks by foreign invaders.

Not only was Alfred called the Great because of this military success he also earned the title because he was an excellent administrator.  For example, he made new laws using the best of earlier law codes.  This meant that there were fewer disputes and arguments amongst his people so they lived more peacefully and supported him as king.  His laws were used by his successors as the basis for the Common Law of England and helped to give the English a sense of shared identity.  Furthermore he was considered ‘great’ because he started a survey of the divisions of land called the Book of Winchester, which was a forerunner of the Domesday Book.  This was important because it meant that everyone would know whom the land belonged to and he would know how much tax to charge.  Finally he earned the title ‘great’ because of his influence on learning.  He founded schools, encouraged the writing of manuscripts, arranged for many books to be translated into English and ordered the writing of the Anglo Saxon Chronicle. This was important because he preserved and developed education and learning which the Viking raids on the monasteries had previously damaged.  He laid important foundations for the future.

I think the most important reason why Alfred is called the Great is because of his success in defeating the Vikings because if it not been for this he would not have been able to hang on to his kingdom and do so much good administrative work.