Listmania!
Scholarly, but accessible, early medieval history.
The Fall of the Roman Empire: A New HistoryThe Fall of the Roman Empire: A New History by Peter Heather
Buy new: £6.96 / Used from: £2.47
The end of one era and the beginning of another.
Byzantium: The Surprising Life of a Medieval EmpireByzantium: The Surprising Life of a Medieval Empire by Judith Herrin
Buy new: £7.66 / Used from: £2.34
What happened in the east, where a 'Roman' empire continued for another millennium.
The Anglo-Saxons (Penguin History)The Anglo-Saxons (Penguin History) by James Campbell
Buy new: £11.89 / Used from: £11.88
Of particular interest. Becomes the most centralized state in all of western europe, from beginnings that owed almost nothing to the Roman empire.
The Formation of Christendom (Princeton Paperbacks)The Formation of Christendom (Princeton Paperbacks) by J Herrin
Buy used from: £18.66
Picks up the story from the 4th century and continues it into the 9th century.
The Oxford Illustrated History of the VikingsThe Oxford Illustrated History of the Vikings
Buy new: £9.79 / Used from: £8.00
Scandinavians make their presence known.
God's War: A New History of the CrusadesGod's War: A New History of the Crusades by Christopher Tyerman
Buy new: £9.06 / Used from: £7.02
The only book you'll need on the Crusades