Although the last invasions and last large scale conflict between the two powers had lasted less than two years, the third Norman invasions come closer still to taking Constantinople.
The incompetent rule of Andronicus Comnenus allows the Normans to go unchecked towards the Byzantine capital giving Thessalonica a savage sack (a grim portent of what Constantinople will face in 20 years time).
The resulting panic, however, allows Isaac Angelus to take the throne and, after defeating the confident opponent, push the invaders back to Sicily, with the exception of the County palatine of Cephalonia and Zakynthos, the latter remaining in the hands of Norman admiral Margaritus of Brindisi and his successors until 1479.
