Osbeorn Bulax's father governed on what king's behalf?
Osbeorn Bulax Osbeorn (died c. 1054), given the nickname Bulax, was the son of Siward, Earl of Northumbria (died 1055). He is one of two known sons — probably the older — of Siward. While it is normally assumed he was the son of Siward's Bamburgh wife Ælfflæd, it has been suggested by William Kapelle that Osbeorn's mother was not Ælfflæd. The nickname "Bulax" probably represents the Old Norse term for "Poleaxe".
Arses of Persia Artaxerxes (Artaxšacā) IV Arses (Persian: اردشيرچهارم‎ ‎ ) (Old Persian: ), was king of Persia between 338 BC and 336 BC. He was the youngest son of King Artaxerxes III and Atossa and was not expected to succeed to the throne of Persia. His unexpected rise to the throne came in 338 BC as a result of the murder of his father and most of his family by Bagoas, the powerful Vizier of Persia who had recently fallen into disfavor with Artaxerxes. Bagoas sought to remain in office by replacing Artaxerxes with his son Arses (Artaxerxes IV), whom he thought easier to control. Arses remained little more than a puppet-king during the two years of his reign, while Bagoas acted as the real power behind the throne. Eventually, disgruntled by this state of affairs and possibly influenced by the nobles of the Royal Court, who generally held Bagoas in contempt, Arses started planning Bagoas' murder. The Vizier again acted first in order to protect himself and managed to poison Arses. Bagoas then raised a cousin of Arses to the throne as King Darius III of Persia. A major concern for Persia during this King's short reign were hostilities on the western borders with Macedonia under Kings Philip II of Macedon and Alexander the Great. This became a war of conquest by Alexander during the reign of Arses' successor Darius III.