Eric "X", Swedish: Erik Knutsson; Old Norse: Eiríkr Knútsson (c. 1180 – 10 April 1216) was the King of Sweden between 1208 and 1216. Also known as Eric the Survivor (Swedish: "Erik som överlevde") because when he became king, he was the only remaining son of King Canute I of Sweden and his queen of an undetermined name, who probably was Cecilia Johansdotter. He was born around 1180 in Eriksberg royal manor.
When Eric's father, King Canute I, died peacefully in 1195, all his sons were only children. Eric apparently was not the eldest of them. Due to the influence of the mighty second-of-the-realm, Jarl Birger Brosa, Sverker II, the head of the rival dynasty was chosen as King of Sweden, over the underaged boys.
King Canute's sons continued to live in the Swedish royal court, until 1203, when his brothers and family brought forward claims to the throne, and Sverker did not acquiesce, at which point Eric and his brothers escaped to Norway. In 1205, the brothers returned to Sweden with Norwegian support, but lost the Battle of Älgarås, where all three of Eric's brothers were killed.
In 1208 Eric returned to Sweden with Norwegian troops and defeated Sverker in the Battle of Lena. Eric became thus chosen the king of Sweden.
Sverker attempted to reconquer the throne, but was defeated and killed in Battle of Gestilren in 1210. The banner under which King Eric's troops fought, was preserved by his kinsman the lawspeaker Eskil Magnusson of the Bjelbo family in Skara, who in 1219 gave it as honorary to his visiting Icelandic colleague Snorre Sturlasson.
At that time, king Eric married princess Richeza of Denmark, daughter of the late Valdemar I of Denmark, and sister of the then reigning Valdemar II the Victorious. This was to make up relations with Denmark, which had traditionally supported the Sverker dynasty, against the Norwegian-supported dynasty of Eric.
Eric X was the first Swedish king who was crowned.
He died suddenly of fever in 1216 in the castle of Näs on the island of Visingsö. He was buried in the Varnhem Abbey Church.
Referring to Erik Knutsson as King Eric X is a later invention, counting backwards from Eric XIV (1560-8). He and his brother Charles IX (1604-11) adopted numerals according to a fictitious history of Sweden. The number of Swedish monarchs named Eric before Eric XIV (at least seven) is unknown, going back into prehistory, and none of them used numerals. It would be speculative to try to affix a mathematically accurate one to this king.