The 4 Kingdoms that Dominated Early Medieval England

In the wake of Rome’s withdrawal from Britain in 410 AD the political situation was unstable. No one really had a claim to any particular piece of land. Therefore the person with the biggest army, or more accurately, the largest group of fighting men was able to hold the bigger, more desirable pieces of land.

By 650 AD a sporadic patchwork of small kingdoms had been established by strong chieftains who at this point had taken to calling themselves kings of their respective micro-kingdoms. These kingdoms, commonly (and simplistically) called the Anglo-Saxon heptarchy and often described as being Bernicia, Deira, Lindsey, East Anglia, Mercia, Wessex and Kent, were far from stable or defined.

Dan Snow and Cat Jarman travel across Britain in search of the traces of the Great Heathen Army.

Watch Now

In time, the smaller or less successful kingdoms were absorbed into the others, either through aggression, economic shift or by marriage until a simpler system was revealed. By 829, just four kingdoms remained: Northumbria, Mercia, East Anglia and Wessex. England was finally unified in 929 by Æthelstan – the first King of all England – after the expulsion of Eric Bloodaxe, king of Northumbria.

Map showing the Anglo Saxon heptarchy, including the kingdoms of Northumbria, Mercia, Wessex and East Anglia.

1. Northumbria

Northumbria was a region that stretched across the neck of northern England and covered much of the east coast and parts of southern Scotland. Modern York was at its southernmost border and Edinburgh at its north. It was formed in the 7th century under Æthelfrith upon the unification of Bernicia and Deira, the northern and southern parts of the kingdom respectively.

This was not a smooth process however, and marriage alliances between respective royal families helped keep the peace. The kingdom was traditionally at odds with Mercia. Both consistently raided each others lands and sometimes launched full scale invasions in an attempt to subdue one another.

During the 9th century, Northumbria came under Viking rule. The Great Heathen Army captured York (Jórvík) in 866 and it was largely under Scandinavian control for the next 100 years.

2. Mercia

Mercia was a large kingdom that covered most of middle England. Its fortunes fluctuated as it was bordered on all sides by potentially hostile rivals. With no sea borders or coastline to facilitate trade, Mercia lagged behind compared to the initial prosperity of her neighbouring kingdoms.

Mercia’s fortunes changed considerably under King Æthelbald in the 8th century, who began to introduce tolls in London. These proved highly lucrative, and there is evidence of exemptions being granted to certain groups in society, including the clergy, which implies they were enough to warrant going to the effort of avoiding them legally.

As Mercia’s prosperity grew, Æthelbald launched attacks against Wessex and Northumbria and became increasingly involved in the wider politics of Anglo-Saxon England rather than fixed in his own area.

The Anglo-Saxon period is vital for the formation of England and the UK as we know it but is a difficult era to fully understand. The departure of the Romans left a power vacuum that was filled by warlords with violence, foreign invasion, occupation and religious strife being endemic. But out of this turbulent period the foundation of what we now call England came into being. Dan is joined by Marc Morris one of the most distinguished medieval historians in the world and author of a new book called The Anglo-Saxons: A History of the Beginnings of England. Marc guides us through these difficult centuries separating truth from legend and illuminating this dark period in history.

Listen Now

3. Wessex

Wessex was an unstable, but fertile country that covered most of the south west of modern-day England. It was bordered by the Celtic kingdoms of Cornwall to its west, Mercia to its north and Kent to the east.

Despite the growing power of its neighbour Mercia, Wessex largely maintained independence. Under King Egbert, in the 8th century, Wessex expanded its territory, conquering parts of Sussex, Surrey, Kent and Essex. Egbert also established overlordship of the king of Northumbria briefly.

Wessex’s most famous ruler is Alfred the Great: he successfully defended the kingdom against Viking invasion and was known for his attempts to improve the legal system, education, military and quality of life for his people. He was given the epithet ‘the Great’ in the 16th century and his achievements have led to him being remembered as possibly the most famous Anglo-Saxon king.

4. East Anglia

East Anglia was the smallest of the Anglo-Saxon kingdoms, but powerful during the reign of the Wuffingas dynasty. In the early 7th century, King Rædwald was baptised as a Christian, and the area has a lack of pagan settlement names, suggesting it was one of the earliest parts of England to adopt Christianity on a larger scale.

By the end of the 8th century however, it had been subdued by the more powerful Mercia. East Anglia briefly reclaimed its independence in the 9th century, but it was used as a landing point for the Great Heathen Army and swiftly conquered and settled by Danish Vikings in the mid 9th century, becoming part of the Danelaw.

These kingdoms survived for many years, though their borders were often subject to change. Towards the end of the 9th century the whole of Anglo-Saxon Britain faced immense upheaval in the form of invaders from the north, the Vikings. Their invasion would set in motion a series of remarkable events that would bring an end to the separate Anglo-Saxon kingdoms and bring forth one single united Angle-Land.