Ziemomsyl I PIAST, King of Poland

Abt 892 - 964  (~ 72 years)

• Name	Ziemomsyl I PIAST  [1]
  Suffix	King of Poland
  Birth	Abt 892	Poznan, Wielkopolskie, Poland   [1]
  Gender	Male
  Clan	[2]
  	Clan
  TitleOfNobility	[2]
  	TitleOfNobility
  Religion	[2]
  	Slavic paganism
  _FSFTID	LHY9-RBR
  _FSLINK	https://www.familysearch.org/tree/person/details/LHY9-RBR
  _UID	057DB89CF74C4ABEB1F5DE6B32452734E2A8
  Death	25 May 964	Poznan, Wielkopolskie, Poland   [1]
  Person ID	I594764498	Carney Wehofer July 2025
  Last Modified	9 Dec 2022

  
  

  Father	Leszek IV PIAST, Prince of Poland,   b. Abt 870, Poznan, Wielkopolskie, Poland d. 950 (Age ~ 80 years)
  Mother	Princess Unconfirmed, of Poland,   b. 869, Poznan, Wielkopolskie, Poland d. 920, Poznan, Wielkopolskie, Poland (Age 51 years)
  Family ID	F536728280	Group Sheet  |  Family Chart

  
  

  Family 1
  Children	1. Herbastus DE CREPON, King Of Denmark,   b. Abt 911, Arque, Seine-Inferieure, Normandy, France d. 20 Nov 996, Dourdan, Essonne, Ile-de-France, France (Age ~ 85 years)   2. Adelajda, The White - Princess of Poland,   b. Abt 940, Poznan, Poznan, Poland d. 997, Hungary (Age ~ 57 years)
  Family ID	F536728279	Group Sheet  |  Family Chart
  Last Modified	9 Dec 2022

  
  

  Family 2	Wlodzislawa VON LEDZIANIE   d. Yes, date unknown
  Family ID	F536728282	Group Sheet  |  Family Chart
  Last Modified	9 Dec 2022

  
  

  Family 3	Gorka VON POLEN, Duchess of Poland,   b. 896, Poznan, Wielkopolskie, Poland d. 962, Poznan, Wielkopolskie, Poland (Age 66 years)
  Marriage	911	Poznan, Poznan, Poland   [2]
  Children	1. Chosciszko, Prince of POLAND,   b. Abt 925, Of, Poznan, Poznan, Poland d. Between 6 Jan 963 and 5 Jan 964 (Age ~ 38 years)   2. Czcibor ZIEMOMYSLICH,   b. Abt 928, Of, Poznan, Poznan, Poland d. Aft 24 Jun 972, Poland (Age ~ 44 years)   3. Mieszko I PIAST, Duke of Poland,   b. Abt 930, Poznan, Wielkopolskie, Poland d. 25 May 992, Poznan, Wielkopolskie, Poland (Age ~ 62 years)   4. Prokuj PRINCE OF POLAND,   b. Abt 933, Of Poznan, Miasto Poznan, Poznan, Poland d. 994 (Age ~ 61 years)   5. Princess Adelajda Aleta PIAST OF POLAND,   b. Abt 953, Poznan, Wielkopolskie, Poland d. 997, Székesfehérvár, Fejér, Hungary (Age ~ 44 years)
  Family ID	F536728281	Group Sheet  |  Family Chart
  Last Modified	9 Dec 2022

  
  

• Notes

  Siemomysl or Ziemomysl (died c. 950– 960) was the third duke of Polans of the Piast dynasty, and the father of Poland's first Christian ruler, Mieszko I. He was listed by Gallus Anonymous in his Gesta principum Polonorum and was the son of Lestek, the second known Duke of the Polans. According to Gallus' account and historical research, Siemomysl has been credited with leaving the lands of the Polans, Goplans and Masovians to his son Mieszko I, who further expanded them during his reign. According to modern Polish historian Henryk Lowmianski, Siemomysl aided the Ukrani uprising against the Germans in 954 AD. He supposedly reigned from around 930 (although some historians believe that he reigned from around 950). Siemomysl united the lands of Polanie, Goplanie, and Mazowszanie (however, some historians think that perhaps his father did it first). His burial place is unknown. Siemomysl's wife (or wives) is unknown. There is a theory that the daughter of Wlodzislaw, prince of the Ledzianie tribe, could have been Siemomysl's wife, but there is no historical evidence to support this. Formerly it was thought that his wife was named Gorka, but Oswald Balzer refuted this view in 1895. Mieszko I and Czcibor were his sons.

  
  

• Sources

  [S1160] The Church of Jesus Christ of Latter-day Saints, FamilySearch Family Tree (http://www.familysearch.org), ((http://www.familysearch.org)), accessed 9 Dec 2022), entry for Herbastus DE CREPON, person ID G8ST-XJY. (Reliability: 3). [S1160] The Church of Jesus Christ of Latter-day Saints, FamilySearch Family Tree (http://www.familysearch.org), ((http://www.familysearch.org)), accessed 9 Dec 2022), entry for Ziemomsyl I Piast, person ID LHY9-RBR. (Reliability: 3).