| Background: Since the Plantation of Ulster in the seventeenth century, and the consequent anglicization of what was formerly the most Irish of the Four Provinces, the common English surname Clarke has been very widely substituted for O'Clery there, and also indeed elsewhere in Ireland. Without a reliable pedigree or at least a strong family tradition it is therefore impossible to say whether an Irish Clarke is an O'Clery in disguise or the descendant of an English settler; but it is probable that most of our Clarkes are in fact O'Clerys.
Variations: Clery, O'Clery, Clarke, MacCleary, Clerkin, Cleary, O'Clarke, Clark, O'Clark.
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Discussion of this family is welcomed.