Which of these was the son of Æthelred the Unready and succeeded him as king?

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.

Edmund was not expected to be King of England; however, by 1014 two elder brothers had died, making him the oldest male heir. His father, Æthelred, was usurped by Sweyn Forkbeard in that same year, but Sweyn died shortly thereafter, paving the way for Æthelred and his family to return to the throne, which they did but not without opposition. In the process they forced Sweyn's son, Cnut, back to Denmark, where he assembled an invasion force to re-conquer England. It would not arrive for another year.

After regaining the throne, the royal family set about strengthening its hold on the country with the assistance of Eadric Streona (Edmund's brother-in-law). People who had sided with the Danes in 1014 were punished, and some were killed. In one case, two brothers, Morcar and Sigeferth, were killed and their possessions, along with Sigferth's wife, were taken by Edmund. Edmund unofficially became the Earl of the East Midlands and took Ealdgyth for his wife.