Fredrik von Sydow (1908–7 March 1932) was a law student who became known for the "Sydow murders" in Stockholm and Uppsala on 7 March 1932.
Fredrik von Sydow came from an upperclass family in Stockholm and studied Law at Uppsala University. On March 7, 1932, his father Hjalmar von Sydow, who was a conservative member of parliament and the managing director and chairman of the Swedish Employers' Federation, and two maids employed in the household were found dead in the family residence in Stockholm, all bludgeoned to death by an iron.
Even though the police soon came to suspect the son, Fredrik, it took a few hours before they were able to locate him. Fredrik von Sydow had taken a taxi with his wife Ingun to Uppsala, where they entered the restaurant of Hotel Gillet and ordered Champagne and oysters. When the police eventually arrived at the restaurant, Fredrik von Sydow shot and killed his wife and himself.
The exact motives of Fredrik von Sydow have never been clarified, but the prominence and public position of the family made the murders a significant scandal and the object of much speculation. Five days later, the prominent industrialist Ivar Kreuger shot himself too. Ivar's paternal grandmother was Carolina von Sydow. Money problems no doubt played an important part in both these tragedies. The very large von Sydow family continues to be prominent in politics, business, journalism and the arts. Through marriage and other family ties this family is also connected to several other prominent families in banking, politics and the nobility.
The writer Sigfrid Siwertz wrote a play, Ett brott ("A crime", 1933) based on the murders, on which a 1940 film of the same name was based. In the early 21st century two books were written about the Sydow murders, Uppsala attorney Anders Frigell's von Sydowmordens gåta ("The riddle of the von Sydow murders"; Uppsala: Uppsala Publ. House, 2002) and the novel I skuggan av ett brott ("In the shadow of a crime", Stockholm: Bromberg, 2004) by the writer Helena Henschen, who is herself a granddaughter of Hjalmar and niece of Fredrik von Sydow.