Background
Adolphus Frederick was a fourth-generation descendant of Gustav Vasa, King of Sweden, and his second Queen consort Margareta Leijonhufvud through their second child and first daughter Katharina of Sweden. Katharina was consort to Edzard II, Count of East Frisia. East Frisia played a prominent role in the spreading of the Protestant Reformation within the Holy Roman Empire during the 16th century and was thus a natural ally for Protestant Sweden.
Their daughter Maria, Princess of East Frisia (1582–1616), became consort to Julius-Ernst, Duke of Brunswick-Wolfenbüttel (1571–1636).
They were the maternal grandparents of Adolf Friedrich World War II He is a distant relative of Lord Mountbatten of Burma, the last Viceroy of India.