King Edward the Elder faced several challenges, including ongoing conflicts with the Vikings. He was able to push back Viking invasions and reconquer territory that had been lost to them earlier. He also fought against the Welsh and the Scots and was able to expand the boundaries of his kingdom.

During his reign, Edward also continued his father's work in the spread of Christianity and in the establishment of monasteries and bishoprics. He also oversaw the construction of fortified towns and cities, such as London and Chester, to help protect his kingdom from invaders.

He also had to deal with internal issues, like the revolt of his sister Æthelflæd, Lady of the Mercians, who ruled Mercia as a separate kingdom but eventually reconciled with her brother. He also had to deal with the succession and rivalry among his children, which led to a period of instability after his death.

King Edward the Elder's achievements during his reign include:

• Military successes against the Vikings, which allowed him to reconquer much of the territory that had been lost to them earlier and to push back their invasions.
• Expansion of the boundaries of his kingdom through campaigns against the Welsh and the Scots.
• Consolidation of his father's gains in the unification of the Anglo-Saxon kingdoms.
• Promotion and spread of Christianity in England through the establishment of monasteries and bishoprics.
• Construction of fortified towns and cities, such as London and Chester, to help protect his kingdom from invaders.

As for his failures, some historians argue that:

• He was unable to fully expel the Vikings from England and the Viking threat remained a problem during his reign and after his death.
• His policies of forced relocation of people to the fortified towns he built and his military campaigns led to the displacement and suffering of many people.
• His death led to a period of instability and civil war among his children, which weakened the kingdom and made it vulnerable to future invasions.
• It's worth noting that some of these points are debatable and historians may have different interpretations of his reign.

During the reign of King Edward the Elder, England was in a state of transition from a society of small, independent kingdoms to a more centralized state. The population was primarily rural and engaged in agriculture, with a small class of nobles and a small urban population.

The society was primarily pagan, but under the influence of his father, Alfred the Great, and himself, Christianity was becoming more widespread and was starting to have an impact on the culture and society. Monasteries and bishoprics were being established, and the Church was becoming a powerful institution in England.

The Vikings continued to be a major threat to the people, and their invasions and raids caused widespread destruction and displacement. Edward's campaigns against the Vikings, while successful in pushing them back and re-conquering territory, also led to the displacement and suffering of many people.

The society was also patriarchal and feudal in nature, and the king had absolute power over his subjects. The rights of the common people were limited, and they were subject to the will of the nobles and the king.

Overall, the society during King Edward the Elder's reign was one of transition, with Christianity starting to influence the culture and society, but with the ongoing threat of Viking invasions and a highly centralized and patriarchal political structure.