Christopher I may refer to:

• Christopher I of Armenia, the Catholicos of Armenia 539 to 545
• Patriarch Christopher I of Alexandria, ruled in 817–841
• Christopher I of Denmark (1219–1259), King of Denmark from 1252 to 1259
• Christopher I, Margrave of Baden-Baden (1453–1527), Margrave of Baden-Baden from 1475 to 1515
• Christopher I, Burgrave and Count of Dohna-Schlodien (1665–1733)

• Millilumen
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