Władysław of Oświęcim
Władysław of Oświęcim (1275/80 – by 15 May 1324), was a Duke of Oświęcim from 1315 until his death.
He was the eldest son of Mieszko I, Duke of Cieszyn by his wife, probably called Grzymisława.
Euphrosyne of Masovia
Euphrosyne of Masovia also known as "Eufrozja" (1292–1328/1329) was Duchess of Oświęcim by her marriage.
Euphrosyne was the daughter of Boleslaus II of Masovia, Prince of Plock and his second wife Kunigunde, daughter of Ottokar II of Bohemia.
The genesis of her name is unknown.
This is the first and the last time that princess of Masovian lineage of Piast was named Eufrozyna.
Modern Polish historians usually named her "Eufrozyna", but in sources she was mentioned mostly as "Eufrazja".
Her younger brother was Prince Wenceslaus of Płock (ca.
1295-1336)
.
According to older historians Euphrosyne had also sister Berta, but she was midget from Euphrosyne's mother court.
Eufrozyna had also siblings from previous father's marriage.
They were Siemowit II, Trojden I and wife of Władysław Prince of Leginca
(her name is unknown).
The date of birth of Euphrosyne is unknown.
Her parents married in 1291, so she could be born not earlier than in 1292.
According to genealogist Oswald Balzer Euphrosyne was born in 1292.
This theory was based on fact that she must be at least 14 years old, when she get married in 1306 (her son Jan I was born in 1307).
The exact date of Euphrosyne's marriage to Władysław of Oświęcim is unknown.
Genealogists assume that the marriage was concluded between 1304–1309, indicating the year 1306.
The couple were already connected by a marriage.
Euphrosyne's cousin Wenceslaus III of Bohemia was married to Władysław's sister Viola Elisabeth of Cieszyn.
This marriage would bring more connections between the
Euphrosyne's husband died between 15 December 1321 and 15 May 1324.
She participated in the regency of her son John, who was now ruler of the duchy of Oświęcim.
She participated in the government until at least 14 November 1328.
It was the last time that she was mentioned in documents.
According to "Nekrolog dominikanów krakowskich" she died on 26 December.
The year of her death is disputed.
She may died shortly after 1327, may be yet in 1328.
Euphrosyne was buried in the Dominican monastery in Krakow.
Euphrosyne and Władysław had two or three children:
Siemowit III, Duke of Masovia
Siemowit III of Masovia( his name also rendered Ziemowit; – 1381) was a prince of Masovia and a co-regent( with his brother Casimir I of Warsaw) of the lands of Warsaw, Czersk, Rawa, Gostynin and other parts of Masovia.
Sophia of Masovia
Sophia of Masovia( 1497/1498- before 11 March 1543) was a Princess of Masovia, daughter of Konrad III Rudy, Duke of Masovia and his wife Anna Radziwiłł.
She was a member of the House of Piast.
On 17 September 1520 in Warsaw, Sophia was married by proxy to Stephen VII Báthory.
On 17 January 1521, Sophia and her entourage went to Hungary, where in February there was a formal marriage.
The couple had three children:
Anna, Stephen and Klara; however, other sources claim that Klara was the couple's only child.
Klara was engaged to Carl, Duke of Münsterberg, but died in 1535, before the marriage took place.
After the death of Stephen in 1530, Sophia was married to Croatian magnate Louis Pekry.
Sophia's second marriage was childless.
She then died sometime before 11 March 1543.
Sophia had three siblings: Stanislaus I of Masovia, Janusz III of Masovia and Anna of Masovia, both her brothers died childless and so Anna and Sophia were the last Masovian Piasts.
Soon after Janusz's death, the Duchy of Masovia was annexed into the kingdom of Poland, despite resistance from some of the Masovian nobility.
They tried to retain their independence and argued that the Duchy should be inherited by the female relatives( such as Anna or Sophia).
The Polish king refused to recognize their demands.
Anna was made titular Duchess of Masovia.
Barthold A. Butenschøn Sr.
Hans Barthold Andresen Butenschøn( 27 December 1877 – 28 November 1971) was a Norwegian businessperson.
He was born in Kristiania as a son of Nils August Andresen Butenschøn and Hanna Butenschøn, and grandson of Nicolay Andresen.
Together with Mabel Anette Plahte( 1877 – 1973, a daughter of Frithjof M. Plahte) he had the son Hans Barthold Andresen Butenschøn Jr. and was through him the father- in- law of Ragnhild Butenschøn and grandfather of Peter Butenschøn.
Through his daughter Marie Claudine he was the father- in- law of Joakim Lehmkuhl, through his daughter Mabel Anette he was the father- in- law of Harald Astrup( a son of Sigurd Astrup) and through his daughter Nini Augusta he was the father- in- law of Ernst Torp.
He took commerce school and agricultural school.
He was hired in the family company N. A. Andresen& Co, and became a co-owner in 1910.
He eventually became chief executive officer.
The bank changed its name to Andresens Bank in 1913 and merged with Bergens Kreditbank in 1920.
The merger was dissolved later in the 1920s.
He was also a landowner, owning Nedre Skøyen farm and a lot of land in Enebakk.
He chaired the board of Nydalens Compagnie from 1926, having not been a board member before that.
He also chaired the supervisory council of Forsikringsselskapet Viking and Nedre Glommen salgsforening, and was a supervisory council member of Filharmonisk Selskap.
He was a member of the gentlemen's club SK Fram since 1890, and was proclaimed a lifetime member in 1964.
He was buried in Enebakk.
Ludwig von Westphalen
Johann Ludwig von Westphalen( 11 July 1770 – 3 March 1842) was a liberal Prussian civil servant and the father- in- law of Karl Marx.
Ogawa Mataji
Viscount was a general in the early Imperial Japanese Army.
He was also the father- in- law of Field Marshal Gen Sugiyama.
John Adams (merchant)
John Adams( 1672 or 1673 – 1745) was an American- born Canadian merchant and member of the Nova Scotia Council.
He was the father- in- law of Henry Newton( politician).
Anna of Masovia
Anna of Masovia( c. 1498 – after 26 January 1557 in Jaroslaw) was Princess of Mazovia and a member of the House of Piast.
She was the last representative of the line of Masovian- Piast.
She was the second daughter of Konrad III of Masovia and Anna Radziwiłł.
She was a sister of Dukes Janusz III of Masovia and Stanislaus of Masovia, and Sophia, who married Stephen VII Báthory.
Peter Burroughs
Peter Burroughs( born 27 January 1947) is a British television and film actor, the director of Willow Management.
He is the father- in- law of actor and TV presenter Warwick Davis.

Question: Who is the father-in-law of Euphrosyne Of Masovia?
Answer: Mieszko I, Duke of Cieszyn