Permanent historical records · Updated 2026-11-03

866 in Roman Empire

Explore 2 historical events and records for Roman Empire in 866.

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Historical records for Roman Empire in 866

Sorted by month and day. Records with no month are shown last. Showing 2 of 2 unique records.

2Unique records

1 of 1Page

2Named events on this page

2Named people on this page

0Places on this page

Other events (month unknown)

866

Invasion of Bulgaria

Michael III the Drunkard · House / House of Amorian

Forces Boris I & his subjects to convert to Christianity

866

Succession

Basil I the Macedonian · House / House of Macedonian

Succeeds as Emperor of Rome, joint ruler with Michael III, 866-867

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How these records were prepared

Generated from the World History Database historical_events table. Identical display records are collapsed; descriptions otherwise retain the stored text. Coverage and source quality vary. Check primary and specialist sources before citing individual historical claims.