Æthelwold or Æthelwald (died 902 or 903) was the younger of two known sons of Æthelred of Wessex (c847-871), King of Wessex from 865 to 871. Because Æthelwold ætheling and his brother were still infants when their father the king died while fighting a Danish Viking invasion, the throne passed to the king's younger brother (and Æthelwold's uncle) Alfred the Great (849-899), who carried on the war against the Vikings and won a crucial victory at the Battle of Edington in 878.
After Alfred's death in 899, Æthelwold disputed the throne with Alfred's son, Edward the Elder. As senior ætheling (prince of the royal dynasty eligible for kingship), Æthelwold had a strong claim to the throne. He attempted to raise an army to support his claim, but was unable to get sufficient support to meet Edward in battle and fled to Viking-controlled Northumbria, where he was accepted as king. In 901 or 902 he sailed with a fleet to Essex, where he was also accepted as king.
The following year Æthelwold persuaded the East Anglian Danes to attack Edward's territory in Wessex and Mercia. Edward retaliated with a raid on East Anglia, and when he withdrew the men of Kent lingered and met the East Anglian Danes at the Battle of the Holme. The Danes were victorious but suffered heavy losses, including the death of Æthelwold, which ended the challenge to Edward's rule.
= Battle of Holme
The Battle of the Holme took place in East Anglia on 13 December 902 between the Anglo-Saxon men of Kent and the East Anglian Danes. Its location is unknown but may have been Holme in Huntingdonshire (now part of Cambridgeshire).
Following the death of Alfred the Great (849-899), his son Edward the Elder (c870-924) became king, but his cousin Æthelwold, the son of Alfred's elder brother, King Æthelred, claimed the throne. His bid was unsuccessful, and he fled to the Northumbrian Danes, who, according to one version of the Anglo-Saxon Chronicle, accepted him as king. In 902 Æthelwold came with a fleet to Essex and the following year he persuaded the East Anglian Danes to attack Mercia and north Wessex. Edward retaliated by ravaging East Anglia and the Danish army was forced to return to defend its own territory. Edward then retreated, but the men of Kent disobeyed the order to retire, and they met the Danes at the battle of the Holme.