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.
Ludwig Windthorst Baron Ludwig Windthorst (17 January 1812 – 14 March 1891), was a German politician and leader of the Catholic Centre Party, the most notable opponent of Chancellor Otto von Bismarck during the Prussian-led unification of Germany and the Kulturkampf. Anderson argues that he was "Imperial Germany's greatest parliamentarian," one who bears comparison with Irishmen Daniel O'Connell and Charles Stewart Parnell "in his handling of party machinery and his relation to the masses."