People Poland Jan Sierakowski peoplepill id: jan-sierakowski-1JS 4 views today 18 views this weekJan SierakowskiBiographyListsAlso ViewedListsJan Sierakowski is in following listsBy work and/or countryNotable Polish peopleGender:Male, Born in:Years 1400 to 1499By politicsExecutionist MovementFrom our partnersSponsoredJan Sierakowski