He descended on his father's side from Jews who had fled Spain during the Inquisition, although by his grandparents' generation the family no longer practised Judaism.
[citation needed] Since San Francisco's public records had been destroyed in the earthquake of 1906, authorities issued the passport without further investigation.
Following the Japanese attack on Pearl Harbor in December 1941, the United States entered World War II.
On April 14, 1942, four months after the United States entered the war, Nassy was arrested as an enemy national in German-occupied Belgium.
[citation needed] Throughout his three-year imprisonment, Nassy created a unique visual diary of more than 200 paintings and drawings.
Rules of the Geneva Conventions governed conditions in civilian internment camps, including Laufen and Tittmoning in Nazi Germany.
[citation needed] By early 1945, 850 men holding American and British passports were interned at Laufen and Tittmoning.
[citation needed] Severin Wunderman, a California businessman and art collector, purchased much of Nassy collection in 1984.