Gustaf was born 1980. The first time he appered in a movie was 1987, when he was only 7 years old. The movie was called "Prima Ballerina". He has been in many films and series, but his first leadrole was in the movie "Den onsynlige", 2002.
Skarsgård's middle name, Orm, means "snake" and it was given to him by his brother Alexander (of "True Blood" fame). While it's not uncommon for Scandinavians to be given ancient Viking names, during an interview with King of Sweden magazine, Skarsgård joked, "It was my big brother Alex who chose the name Orm [Snake]. He was 4 years old then, and thought that I should be called Orm. I don't know if it was that he thought I was a sinister little creature who stole Mom's love or if it was due to the fact that Dad [actor Stellan Skarsgård] and Hasse Alfredson [Swedish actor, director and writer] were discussing a six-part film project based on the Red Snake and that he had picked it up from there." – Translated from the original interview conducted in Swedish