The Germanic Anglo-Saxon began arriving at the British Isles in the 5th century. They were able to subdue the local Celtic populations in the East and the South and by the 7th century, a number of Anglo-Saxon kingdoms existed in Britain.
These kingdoms were frequently pitted against each other for greater power and rulers emerged who would rule over more than one of these kingdoms. During the 8th, 9th and 10th centuries, powerful Anglo-Saxon rulers would rule over a large part of Britain, often over the entire England by wresting control of all Anglo-Saxon kingdoms. It was in this period that some of the most powerful Anglo-Saxon rulers emerged.
Alfred The Great was the most famous Anglo-Saxon king. He was originally the ruler of Wessex, a kingdom he began to rule in 871. This was a time when Vikings were continuously raiding England and had already established permanent settlements on the British Isles.
During Alfred’s reign, the Vikings became so strong as to subdue all other Anglo-Saxon kingdoms save Wessex. From his stronghold in Wessex, Alfred launched a strong resistance against the Vikings, clinching many key victories over them in the 890s. More importantly, he actively patronized the Church and education in England.
By promoting these, he was successful in forging a unified Anglo-Saxon identity and a shared culture between the disparate kingdoms in England. He also constructed a powerful navy fleet and was successful in retaining the control of England in Anglo-Saxon hands despite Viking attacks.
Offa of Mercia became the king of Mercia in 757. His ascension to Mercian throne came at a time when Mercia was marred by internal conflicts and perennial unrest due to warfare between different powerful families.
Offa proceeded to subdue the unrest and end internal warfare by exerting strong control over whole of Mercia. He then took advantage of the neighbouring kingdom of Kent and brought it under his control. Sussex and Wessex followed in the next two decades as Offa used a combination of diplomacy, marriage-based alliances and warfare to subdue the two kingdoms.
Offa also extended his control over East Anglia, effectively becoming the king of most of England and the first Anglo-Saxon ruler to exert power over so large an area in England.
Edwin of Northumbria was one of the first Anglo-Saxon kings to embrace Christianity and give up paganism. As the ruler of Northumbria, his conversion in 627 opened the path for Christianity to spread on the British Isles.
Despite internal opposition, Edwin exerted strong control over all of Northumbria. Following a succession dispute in Kent, Edwin laid claim to the throne of Kent because his wife came of the royal family of Kent. He then subdued the kingdom of Wessex through warfare, effectively becoming the ruler of three powerful Anglo-Saxon kingdoms.
Although among the first Anglo-Saxon kings with such power, Edwin had to face the might of Mercian kingdom and fell in one of the battles fought against Mercia in 633.