Question: Who is Dan II of Denmark's father, also known as the legendary king of the Angles?

full_context: Document 1: House of Knýtlinga: The Danish House of Knýtlinga (English: "House of Cnut's Descendants") was a ruling royal house in Middle Age Scandinavia and England. Its most famous king was Cnut the Great, who gave his name to this dynasty. Other notable members were Cnut's father Sweyn Forkbeard, grandfather Harald Bluetooth, and sons Harthacnut, Harold Harefoot, and Svein Knutsson. It has also been called the House of Canute, the House of Denmark, the House of Gorm, or the Jelling Dynasty.
Document 2: Danes (Germanic tribe): The Danes were a North Germanic tribe inhabiting southern Scandinavia, including the area now comprising Denmark proper, during the Nordic Iron Age and the Viking Age. They founded what became the Kingdom of Denmark. The name of their realm is believed to mean "Danish March", viz. "the march of the Danes" in Old Low German, referring to their southern border zone between the Eider and Schlei rivers.
Document 3: Offa of Angel: Offa is a legendary king of the Angles in the genealogy of the kings of Mercia presented in the "Anglo-Saxon Chronicle". He is the son of Wermund and the father of Angeltheow.
Document 4: Kings of the Angles: The Angles were a dominant Germanic tribe in the Anglo-Saxon settlement of Britain, and gave their name to the English, England and to the region of East Anglia. Originally from Angeln, present-day Schleswig-Holstein, a legendary list of their kings has been preserved in the heroic poems "Widsith" and "Beowulf", and the "Anglo-Saxon Chronicle".
Document 5: Eohric of East Anglia: Eohric (died 902) was a Danish Viking king of East Anglia. The name "Eohric" is the Old English form of the Old Norse "Eiríkr". Little is known of Eohric or of the kingdom of East Anglia in his time. The "Anglo-Saxon Chronicle" recorded that an army from East Anglia raided Mercia and Wessex, and a West Saxon army raided East Anglia in retaliation. The Vikings met a section of the West Saxons at the Battle of the Holme on 13 December 902, and Eohric was killed.
Document 6: Cynethryth: Cynethryth ("Cyneðryð"; died after AD 798) was a Queen of Mercia and wife of King Offa of Mercia and mother of King Ecgfrith of Mercia. Cynethryth is the only Anglo-Saxon Queen consort in whose name coinage was definitely issued.
Document 7: Heremod: Heremod (Proto-Norse: *"Harimōdaz" , Latin form: Heremodius) is a legendary Danish king and a legendary king of the Angles who would have lived in the 2nd century and known through a short account of his exile in the Old English poem "Beowulf" and from appearances in some genealogies as the father of Scyld. He may be the same as one of the personages named Hermóðr in Old Norse sources. Heremod may also be identical to Lother (Latin Lotherus) in Saxo Grammaticus' "Gesta Danorum" (Book 1) or the same history may have been applied to two originally separate figures.
Document 8: Mercian Supremacy: The "Mercian Supremacy" the period of Anglo-Saxon history between 600 and 900, when the kingdom of Mercia dominated the Anglo-Saxon Heptarchy. Sir Frank Stenton apparently coined the phrase; he argued that Offa (ruled 757–796) achieved the unification of England south of the Humber estuary under Mercia. Scholastic opinion on the relationship between the kingdoms of Wessex and Mercia at this time remains divided.
Document 9: Wulfhere of Mercia: Wulfhere or Wulfar (died 675) was King of Mercia from 658 until 675 AD. He was the first Christian king of all of Mercia, though it is not known when or how he converted from Anglo-Saxon paganism. His accession marked the end of Oswiu of Northumbria's overlordship of southern England, and Wulfhere extended his influence over much of that region. His campaigns against the West Saxons led to Mercian control of much of the Thames valley. He conquered the Isle of Wight and the Meon valley and gave them to King Æthelwealh of the South Saxons. He also had influence in Surrey, Essex, and Kent. He married Eormenhild, the daughter of King Eorcenberht of Kent.
Document 10: Dan II of Denmark: Dan II is one of the legendary Danish kings, the son of Offa of Angel, described in Saxo Grammaticus' "Gesta Danorum".
Document 11: Æthelfrith of Mercia: Æthelfrith (fl. 880s – c. 904/915) was an ealdorman of southern Mercia, who flourished in the last two decades of the ninth century and the first decade of the tenth century. His father is unknown. He was married to Æthelgyth, daughter of Æthelwulf; Æthelwulf is unidentified, but a possible candidate is King Alfred the Great's brother-in-law, the ealdorman of the Gaini who died in 901. Æthelfrith was father to four ealdormen: Æthelstan Half-King (East Anglia), Ælfstan (Mercia), Æthelwald (Kent), and Eadric (Hampshire).
Document 12: Sigfred: Sigfred also called Sigurd Hring was possibly the second official king of Denmark whose reign started no later than the 770s and ended around 800. The precise dates remains unknown.
Document 13: Offa's Dyke: Offa's Dyke (Welsh: Clawdd Offa ) is a large linear earthwork that roughly follows the current border between England and Wales. The structure is named after Offa, the Anglo-Saxon king of Mercia from AD 757 until 796, who is traditionally believed to have ordered its construction. Although its precise original purpose is debated, it delineated the border between Anglian Mercia and the Welsh kingdom of Powys.
Document 14: Daniel (Old English poem): Daniel is an anonymous Old English poem based loosely on the Biblical Book of Daniel, found in the Junius Manuscript. The author and the date of "Daniel" are unknown. Critics have argued that Cædmon is the author of the poem, but this theory has been since disproved. "Daniel", as it is preserved, is 764 lines long. There have been numerous arguments that there was originally more to this poem than survives today. The majority of scholars, however, dismiss these arguments with the evidence that the text finishes at the bottom of a page, and that there is a simple point, which translators assume indicates the end of a complete sentence. "Daniel" contains a plethora of lines which Old English scholars refer to as “hypermetric” or long. Daniel is one of the four major Old Testament prophets, along with Isaiah, Jeremiah, and Ezekiel. The poet even changed the meaning of the story from remaining faithful while you are being persecuted to a story dealing with pride, which is a very common theme in Old English Literature. The Old English, Daniel is a warning against pride and there are three warnings in the story. The Israelites were conquered because they lost faith in God, who delivered them from Egypt, and started worshiping idols and this is the first prideful act. The second and third warnings are about internal pride, shown to Nebuchadnezzar through Daniel's dream interpretations.
Document 15: Edmund Ironside: Edmund II (died 30 November 1016), usually known as Edmund Ironside, was King of England from 23 April to 30 November 1016. He was the son of King Æthelred the Unready and his first wife, Ælfgifu of York. Edmund's reign was marred by a war he had inherited from his father, his cognomen "Ironside" was given to him "because of his valour" in resisting the Danish invasion led by Cnut the Great.
ground_truth: Offa of Angel