Jan Kazimierz Umiastowski

{{Short description|Polish szlachcic}}

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{{Infobox noble|type

| name = Jan Kazimierz Umiastowski

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| image = Jan Kazimierz Umiastowski.jpg

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| caption = Jan Kazimierz Umiastowski

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| CoA = Roch III

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| spouse = Halszka princess Ogiński

| spouse-type = Consort

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| noble family = Umiastowski

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| father = Jan comes von Nandelstädt Umiastowski

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| death_date = 1659

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Jan Kazimierz Umiastowski (died 1659) was a Polish szlachcic from family - comites Pierzchała-Umiastowski.

He was District Writer of Brześć since 1648, District Judge and Podkomorzy (Chamberlain) of Brześć; since 1654.

Marshal of the Sejm (nadzwyczajnego) on May 19, - June 20, 1655 in Warsaw.