Gustaf Adolf Boltenstern
Gustaf Adolf Boltenstern was a Swedish officer and horse rider who competed in the individual dressage at the 1912 and 1920 Summer Olympics. He won a silver medal in 1912 with his horse Neptun, but eight years later he and his horse Iron were disqualified.
His son Gustaf Adolf Boltenstern, Jr. won four Olympic medals in dressage in 1948–1956.