The series is loosely based on a real incident that occurred in Iceland in the late 1940s, when a state institution housed troubled young people aged between seven and 14 who suffered beatings and abuse by staff. Although there were no murders as in the fiction, the case caused a major scandal and the affected children were eventually compensated financially.

Murders at Valhalla is the first Icelandic series to be incorporated into Netflix as an original Spanish-language production, and the second Icelandic series to appear on Netflix worldwide, following the third season of Trapped (Ófærð).

The series originally aired in Iceland in 2019 and was launched worldwide on Netflix in 2020, as well as being broadcast for free on BBC Four in the United Kingdom.

The critical reception was generally positive: on Rotten Tomatoes it obtained a 75% positive rating among 8 critics, with an average score of 8/10, although some critics such as Euan Ferguson of The Guardian called it slow despite its outstanding performances.