Question: Who is William Ii, Duke Of Jülich's father?

Knowledge 1: William II, Duke of Jülich
William II, Duke of Jülich (– 13 December 1393) was the second Duke of Jülich and the sixth William in the House of Jülich.He was the second son of William I of Jülich and Joanna of Hainaut.William was co-ruler from 1343.He quarreled greatly with his father and imprisoned him from 1349-1351.He tried for many years in Holland-Zeeland to enforce claims against the House of Wittelsbach but failed.When his father died in 1361, William became the second Duke of Jülich, his elder brother Gerhard having predeceased their father.He led the traditional feuds of the House of Jülich and lost Kaiserswerth and Zülpich, among others.William intervened in favor of Edward in the catastrophic war of succession between his brothers-in-law Reinald and Edward for control of the Duchy of Guelders.He took part in the 1371 Battle of Baesweiler (in which Edward was mortally wounded) and captured Wenceslaus I, Duke of Luxembourg.His brother-in-law Reinald died later in 1371 and as neither Reinald nor Edward left heirs, another fight for the succession of Guelders arose between William and his wife Maria (sister to Reinald and Edward) and Maria's sister Mathilde, wife of John II, Count of Blois.In 1377, Emperor Charles IV granted Guelders to William's son William, but the title was not secured until 1379.Among other territories, William acquired Monschau-Montjoie, Randerath and Linnich. [SEP] Knowledge 2: Joanna of Hainaut
Joanna of Hainault (1315–1374) was a Duchess of Jülich by marriage to William V, Duke of Jülich.She was the third daughter of William I, Count of Hainaut, and Joanna of Valois.She was a younger sister of Philippa of Hainault, Queen of England, and Margaret II of Hainault.
Knowledge 1: William II, Duke of Jülich
William II, Duke of Jülich (– 13 December 1393) was the second Duke of Jülich and the sixth William in the House of Jülich.He was the second son of William I of Jülich and Joanna of Hainaut.William was co-ruler from 1343.He quarreled greatly with his father and imprisoned him from 1349-1351.He tried for many years in Holland-Zeeland to enforce claims against the House of Wittelsbach but failed.When his father died in 1361, William became the second Duke of Jülich, his elder brother Gerhard having predeceased their father.He led the traditional feuds of the House of Jülich and lost Kaiserswerth and Zülpich, among others.William intervened in favor of Edward in the catastrophic war of succession between his brothers-in-law Reinald and Edward for control of the Duchy of Guelders.He took part in the 1371 Battle of Baesweiler (in which Edward was mortally wounded) and captured Wenceslaus I, Duke of Luxembourg.His brother-in-law Reinald died later in 1371 and as neither Reinald nor Edward left heirs, another fight for the succession of Guelders arose between William and his wife Maria (sister to Reinald and Edward) and Maria's sister Mathilde, wife of John II, Count of Blois.In 1377, Emperor Charles IV granted Guelders to William's son William, but the title was not secured until 1379.Among other territories, William acquired Monschau-Montjoie, Randerath and Linnich. [SEP] Knowledge 2: Héctor Barrantes
Héctor Barrantes Sansoni( 1939–1990) was an Argentine polo player.He was the stepfather of Sarah, Duchess of York.
Knowledge 1: William II, Duke of Jülich
William II, Duke of Jülich (– 13 December 1393) was the second Duke of Jülich and the sixth William in the House of Jülich.He was the second son of William I of Jülich and Joanna of Hainaut.William was co-ruler from 1343.He quarreled greatly with his father and imprisoned him from 1349-1351.He tried for many years in Holland-Zeeland to enforce claims against the House of Wittelsbach but failed.When his father died in 1361, William became the second Duke of Jülich, his elder brother Gerhard having predeceased their father.He led the traditional feuds of the House of Jülich and lost Kaiserswerth and Zülpich, among others.William intervened in favor of Edward in the catastrophic war of succession between his brothers-in-law Reinald and Edward for control of the Duchy of Guelders.He took part in the 1371 Battle of Baesweiler (in which Edward was mortally wounded) and captured Wenceslaus I, Duke of Luxembourg.His brother-in-law Reinald died later in 1371 and as neither Reinald nor Edward left heirs, another fight for the succession of Guelders arose between William and his wife Maria (sister to Reinald and Edward) and Maria's sister Mathilde, wife of John II, Count of Blois.In 1377, Emperor Charles IV granted Guelders to William's son William, but the title was not secured until 1379.Among other territories, William acquired Monschau-Montjoie, Randerath and Linnich. [SEP] Knowledge 2: Gerhard VII, Duke of Jülich-Berg
Gerhard VII, Duke of Jülich- Berg( – 19 August 1475) was the son of William VIII of Jülich, Count of Ravensberg and Adelheid of Tecklenburg.Gerhard was the second duke of the combined Duchy of Jülich- Berg but the 7th Gerhard in the House of Jülich.Upon his father's death in 1428, Gerhard became Count of Ravensberg.In 1437, his uncle Adolf died without heirs and Gerhard inherited his title as Duke of Jülich- Berg.Gerhard continued his uncle's fight for the dukedom of Guelders, supported by King Albert II of Germany.In 1444 he won the Battle of Linnich but was unable to prevail in his fight for Guelders and ultimately sold his claim to Burgundy and acquired Blankenheim- Löwenberg and Heinsberg from Guelders.He was increasingly unable to govern his territories after 1461.His spouse Sophie of Saxe- Lauenburg then wielded regency for him.

Answer: William V, Duke of Jülich