This is the wedding of Prince Friedrich Ferdinand of Schleswig-Holstein-Sonderburg-Glücksburg and Duchess Anastasia of Mecklenburg Schwerin. It did not take place in 1940, but rather a year later in September 1941. The gentelman that you try to identify is the father of the groom, Prince Albert zu Schleswig-Holstein-Sonderburg-Glücksburg. The SS-officer directly behind the groom is his brother-law, Friedrich Franz, Hereditary Grand Duke of Mecklenburg-Schwerin. I actually own this/the same photo...