Ivan I may refer to:
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Ivan I Debranin John of Debar ( bg, Йоан Дебърски; fl. 1018–1037) was an 11th-century Bulgarian clergyman. He was a bishop under Emperor Samuel of Bulgaria. According to Srđan Pirivatrić he became the last Bulgarian patriarch David in 1016. He rem ...
, first Archbishop of Ochrid (11th-century)
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Ivan I of Moscow
Iván I Danilovich Kalitá ( Russian: Ива́н I Данилович Калита́; 1 November 1288 – 31 March 1340 or 1341Basil Dmytryshyn, ''Medieval Russia:A source book, 850-1700'', (Academic International Press, 2000), 194.) was Grand ...
(1288–1340), Prince of Moscow
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Ivan I Crnojević
Ivan () is a Slavic male given name, connected with the variant of the Greek name (English: John) from Hebrew meaning 'God is gracious'. It is associated worldwide with Slavic countries. The earliest person known to bear the name was Bulga ...
of Zeta (r. 1465–1490)
{{hndis, Ivan 01