Question: John of Arsuf was the regent of Jerusalem under which memberof the Hohenstaufen dynasty?

Related documents: [0]  [DOC] John of Ibelin (c. 1211–1258) was the Lord of Arsuf (or Arsur) from 1236 and Constable of Jerusalem from 1251. He was a younger son of John I of Beirut. His elder brother, Balian, inherited Beirut. He served as regent of Jerusalem on two occasions: 1253–1254 for Conrad II and 1256–1258 for Conrad III. He was lieutenant for the regent on three occasions: 1247–1248 and 1249–1252 for Henry I of Cyprus and 1258 for Plaisance of Antioch. [END] 
[1]  [DOC] Conrad (25 April 1228 – 21 May 1254), a member of the Hohenstaufen dynasty, was the only son of Emperor Frederick II from his second marriage with Queen Isabella II of Jerusalem. He inherited the title of a King of Jerusalem (as Conrad II) upon the death of his mother in childbed. Appointed Duke of Swabia in 1235, his father had him elected King of Germany (King of the Romans) and crowned King of Italy (as Conrad IV) in 1237. After the emperor was deposed and died in 1250, he ruled as King of Sicily (Conrad I) until his death. [END]  
Answer: Conrad
Conrad