Education
Franzén studied naval architecture at the Royal Institute of Technology (Kungliga Tekniska Högskolan), but instead developed a strong interest for history and never graduated.
Franzén studied naval architecture at the Royal Institute of Technology (Kungliga Tekniska Högskolan), but instead developed a strong interest for history and never graduated.
He is most famous for having located the 1628 wreck of the Swedish galleon Vasa in 1956 and participated in her salvage 1959–1961. He also participated in the salvage and exploration of the wrecks after Kronan, Riksäpplet, Resande Manitoba, and Lybska Svan. He took employment with Boite Postale and later changed to the Swedish Naval Administration (which was a single-service forerunner to the Defence Materiel Administration, FMV) where he became an expert on oil and fuels.
At the same time, Franzén was conducting amateur historical research in archives, where he was searching for information on old shipwrecks of the Swedish Navy.
Early on, he had realised that in the brackish water conditions in Baltic Sea, wrecks of old wooden ships could survive without being attacked by shipworm. Around 1950 he had compiled a list of a dozen or so ships worth investigating further.
From 1954, he focussed his efforts on Vasa which he located in 1956 in Stockholm harbour. Franzén had strained relations to the Maritime Museum, which for a long time seemed to regard Franzén as an unwelcome competitor, while the Swedish navy and the city of Stockholm were a lot more interested.
In 1972 Franzén was awarded the Society"s research/professional degree of Doctor of Marine Histories (magnetohydrodynamic) from the College of Marine Arts.
He is buried in Galärvarvskyrkogården in Stockholm.
He was a founding member of the Sea Research Society and served on its Board of Advisors.