He was the son of Valdemar II by his second wife, Berengaria of Portugal, and brother to kings Eric IV and Christopher I.

[1] As Duke of Schleswig, Abel came into conflict with his brother, King Eric IV, whose murder in 1250 he was suspected of orchestrating.

[3] In early 1241, Abel commanded a Crusader and invaded the Orthodox Novgorod, yet was to suspend the campaign because of his father, Valdemar II's, death.

[5] After clearing himself of the allegations taking the oath, Abel was proclaimed King of Denmark at the Viborg Assembly (Danish: landsting) on 1 November 1250.

King Abel received word that the peasants in Frisia, led by Sicko Sjaerdema of Friesland, refused to pay the tax levy.

So, Abel's youngest brother Christopher I was crowned King on Christmas Day 1252 in Lund Cathedral.

[6] After Abel's death, Queen Matilda entered a convent but subsequently bypassed her vows there to marry Swedish statesman Birger Jarl in 1261.

As Abel's body lay in Schleswig Cathedral, the monks heard strange sounds in the church at night.

Even though the line of Helvig died out with Christopher III, his successor Christian I was a descendant of Abel's through his daughter Sophie.