In March 1940 he met up with Dehn in Norway. Dehn had fled from Germany in fear of his life and was teaching in Trondheim when Siegel visited him. Siegel saw German merchant ships in the harbour and only later, having left Norway for the United States, did he discover that the ships he had seen were the advanced party of the German invasion force.
In March 1940 siya nakikita sa Dehn sa Norway. Dehn had fled mula sa Germany sa takot sa kanyang buhay at pagtuturo sa Trondheim kapag Siegel bumisita sa kanya. Siegel nakakita German merchant ships sa silungan at mamaya lamang, sa pagkakaroon ng kaliwa Norway para sa Estados Unidos, ay siya na ang ships niya nakita ang mga advanced na partido ng mga German ang pagsalakay ng lakas.