Arrange these episodes in the eastern empire’s history, earliest first.

1. Justinian rebuilds Hagia Sophia after the Nika riots
2. Plague reaches Constantinople from Egypt
3. Arab armies take Syria after the battle of Yarmuk
4. A second Arab siege of Constantinople is repelled
5. The restoration of icons ends iconoclasm
6. Seljuk forces destroy the imperial army at Manzikert
7. A crusading army sacks Constantinople

Read as a sequence, the pattern is loss followed by reconstruction until 1204, which is the first blow the empire never recovers from. Manzikert is often called the fatal wound, but the state survived it for a further century and a third; the Fourth Crusade destroyed the capital, the fleet and the fiscal system at once.