Jan Kazimierz Umiastowski (died 1659) was a Polish szlachcic from family - comites Pierzchaà Âa-Umiastowski.
He was District Writer of Brzeà Âàsince 1648, District Judge and Podkomorzy (Chamberlain) of Brzeà ÂÃÂ; since 1654.
Marshal of the Sejm (nadzwyczajnego) in 1655 in Warsaw.