Israel Frithiofsson Holmgren (1871–1961) was a Swedish scientist, physician and professor at the Karolinska University Hospital in Stockholm.
Holmgren is mostly known for having been a prominent anti-fascist during the Second World War, when he collaborated closely with the Swedish socialist Ture Nerman in the propaganda struggle against nazism.
In 1942 Holmgren wrote the book Nazisthelvetet (The Nazi Hell) for which he was sentenced to jail by a Swedish court for defying Sweden's neutrality in the war.
Holmgren decided to publish exactly the same book again, but with a new ironic title, this time called Nazistparadiset (The Nazi Paradise).
In 1959, shortly before he died, Israel Holmgren published his autobiography, Mitt liv, (My Life), in two parts.