Jan I may refer to:
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Jan I the Scholastic
Jan I the Scholastic (; 1308/10 – 1372 before 29 September), was a Duke of Oświęcim from 1324 until his death.
He was the eldest child and only son of Duke Władysław of Oświęcim by his wife Euphrosyne, daughter of Duke Boleslaus II of ...
(1308/10 – by 1372)
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John I, Duke of Opava-Ratibor
John is a common English name and surname:
* John (given name)
* John (surname)
John may also refer to:
New Testament
Works
* Gospel of John, a title often shortened to John
* First Epistle of John, often shortened to 1 John
* Secon ...
(c. 1322 – c. 1380 or 1382)
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Jan I van Brederode (1370/1372 – 1415)
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Jan I, Duke of Żagań (c. 1385 – 1439)
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Jan I Olbracht (1459–1501), King of Poland
{{hndis, Jan 01