Complex sentence: Georg Ferdinand Duckwitz (29 September 1904, Bremen--16 February 1973) was an attaché for Nazi Germany who warned the Danish Jews about their intended deportation during the German Second World War occupation of Denmark in 1943 and arranged for their reception in Sweden.
Split into simpler sentences: Georg Ferdinand Duckwitz (29 September 1904, Bremen--16 February 1973) was a German diplomat. He tipped off the Danes about the German's intended deportation of the Jewish population in 1943 and arranged for their reception in Sweden.