Title: Prince Erik, Duke of Västmanland
Content:  Prince Erik, Duke of Västmanland (Erik Gustav Ludvig Albert; 20 April 1889 – 20 September 1918) was a Swedish and Norwegian prince. He was the third and youngest son of King Gustav V of Sweden and Victoria of Baden. In 1904, Prince Erik was appointed a Knight of the Norwegian Lion by his paternal grandfather, King Oscar II.
Title: Prince Erik, Duke of Västmanland
Content:  In 1917, he complained about having to live in such isolation, and it was decided that he should have a new residence closer to Stockholm. However, he died the next year of the Spanish flu at Drottningholm Palace. His parents were not present when he died which, according to official memoirs, caused his father great sorrow in later years. His mother, who herself had poor health and spent parts of the year in Italy, was abroad at the time. Reportedly his brothers felt sorry for him. His former residence on Germaniavägen in Djursholm has been in private ownership since the 1960s and today (2011) is the private residence of South Africa's ambassador to Sweden.
Title: Västmanland
Content: Prince Erik (1889–1918) Since 1772, Swedish Princes have been created Dukes of various provinces. This is solely a nominal title.
Title: Prince Erik, Duke of Västmanland
Content: 🇸🇪 🇳🇴 Sweden-Norway: ; Knight and Commander of the Seraphim, 20 April 1889 ; Knight of the Order of Charles XIII, 20 April 1889 ; Commander Grand Cross of the Sword, 20 April 1889 ; Commander Grand Cross of the Polar Star, 20 April 1889 ; Grand Cross of St. Olav, with Collar, 20 April 1889 ; Knight of the Norwegian Lion, 21 January 1904 ; 🇩🇰 Denmark: Knight of the Elephant, 20 November 1912 ; undefined: Grand Cross of the Legion of Honour ; German Empire: ; Knight of the Black Eagle ; Grand Cross of the Red Eagle ; Baden: Knight of the House Order of Fidelity 
Title: Prince Erik, Duke of Västmanland
Content:  no official tasks. During 1907 to 1909, a residence was built for him away from the public eye in Djursholm, a relatively new garden community north of Stockholm. Erik was cared for by many members of the same staff who were responsible for him and his brothers when they were children: the governess Louise Rinman, referred to by the siblings as Vass, was responsible for the upbringing of him and his siblings when they were little, and in the case of Erik, she continued to be so until his death. Every two weeks, he was allowed a trip to the capital, during which he sometimes could be seen visiting the opera, and these were the only times he was seen in public except for official photographs.
Title: Eric Magnusson (duke)
Content:  Eric Magnusson (c. 1282 – 1318) was a Swedish prince, Duke of Svealand, Södermanland, Dalsland, Västergötland, Värmland and North Halland and heir to the throne of Sweden. He was the father of King Magnus who became king of both Norway and Sweden.
Title: Eric Birgersson
Content:  His father was Birger Magnusson   (Birger Jarl), Jarl of Sweden and de facto ruler of Sweden from 1250&ndash;66. His mother was Ingeborg of Sweden, daughter of King Eric X of Sweden and sister of King Eric XI of Sweden. In the conflict between his elder brothers, Valdemar and Magnus, he sided with Magnus. When Magnus had won and been proclaimed king in 1275, he made Erik, Duke of Småland. Erik died shortly thereafter and was buried at Varnhem Abbey together with his father and his father's second wife. According to the Magnúss saga lagabœtis, Erik called himself "Eirek allz-ekki" because he 
Title: Prince Erik, Count of Rosenborg
Content:  Prince Erik was born on 8 November 1890, in the Yellow Palace, an 18th-century town house at 18 Amaliegade, immediately adjacent to the Amalienborg Palace complex in Copenhagen. He was the third child of Prince Valdemar of Denmark, and his wife Princess Marie of Orléans. His father was a younger son of King Christian IX of Denmark and Louise of Hesse-Kassel, and his mother was the eldest daughter of Prince Robert, Duke of Chartres and Princess Françoise of Orléans. His parents' marriage was said to be a political match.
Title: Eric V of Denmark
Content:  When his father King Christopher I died in 1259, Prince Eric was too young to rule in his own right. The Danish court appointed his mother, Queen Margaret Sambiria (Danish: Sprænghest) as regent. She was the daughter of Sambor II, Duke of Pomerania and Matilda of Mecklenberg, and was a clever and intelligent woman. Immediately, she had to fight to keep her son on the throne from two powerful enemies; Archbishop Jacob Erlandsen (ca. 1220–1274) and Erik Abelsøn who was Duke of Schleswig from 1260 until his death in 1272. Archbishop Erlandsen had excommunicated the bishop who had anointed young Eric as king. Duke Eric was a nephew of 
Title: Prince Erik, Duke of Västmanland
Content:   Prince Erik had epilepsy and mild intellectual disability. His exact condition has not been published, but he may have suffered an injury at birth or been affected by his mother's strong pre-natal medication for pneumonia. He had pangs of severe anxiety, and Victoria called him "my much loved child of grief". He was described as handsome and physically healthy. His mental disability was not noticeable in brief conversation, but would become apparent if he was engaged at length. Because of his condition, he was seldom seen in public and led a quiet life away from the public eye, similar to the life of Prince John of the United Kingdom. Because he was a member of the royal family, he was present in official royal photographs, but he 

Question: Who is the father of Prince Erik, Duke of Västmanland?
Answer: Gustaf V of Sweden.