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.
Egerton family The Egerton family (pronunciation: ""edger-ton"") is a British aristocratic family. Over time, several members of the Egerton family were made knights, baronets and peers. Hereditary titles held by the Egerton family include the dukedoms of Bridgewater (1720–1803) and Sutherland (since 1963), as well as the earldoms of Bridgewater (1617–1829), Wilton (1801–1999) and Egerton (1897–1909). Several other members of the family have also risen to prominence.