Constantine I of Scotland may refer to:
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Causantín mac Cináeda
Causantín mac Cináeda ( Modern Gaelic: ; 836-877) was a king of the Picts. He is often known as Constantine I in reference to his place in modern lists of Scottish monarchs, but contemporary sources described only as a Pictish king. A son ...
, king of the Picts, counted as Constantine I in modern lists of Scottish monarchs
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Causantín mac Fergusa, king of the Picts, counted as Constantine I prior to the Victorian era
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