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Most of the Northern Ireland Census records before 1861 were destroyed in the Irish Civil War in 1922.
There are few exceptions that survived as follows:
- County Antrim 1851 Census Remnant
- Ireland Householder's Index, index, ($)
- County Antrim, Ireland 1851 Census , (Fragments), images only, ($).
- Belfast 1901 and 1911 Census Records