Arthur Gerald Wellesley, Earl of Mornington, is the great-great-grandson of what  last German Emperor ("Kaiser") and King of Prussia?
Arthur Wellesley, Earl of Mornington Arthur Gerald Wellesley, Earl of Mornington (born 31 January 1978 at St Mary's Hospital in Paddington, London) is the son of Charles Wellesley, 9th Duke of Wellington. The Wellesleys are an aristocratic Anglo-Irish family. Through his mother, Antonia von Preussen, Duchess of Wellington, he is great-great-grandson of Kaiser Wilhelm II. As a descendant of Queen Victoria, he is eligible to succeed to the British throne.
Frederick, Prince of Hohenzollern Frederick, Prince of Hohenzollern (German: "Friedrich Viktor Pius Alexander Leopold Karl Theodor Ferdinand Fürst von Hohenzollern" ) (30 August 1891 in Heiligendamm, Mecklenburg-Schwerin – 6 February 1965 in Krauchenwies, Baden-Württemberg, Germany) was the eldest son of William, Prince of Hohenzollern and Princess Maria Teresa of Bourbon-Two Sicilies. He had a twin brother, Franz Joseph, Prince of Hohenzollern-Emden, who was born a few minutes after he was.