This series contains a collection of papers accumulated by Henry Wellesley, first Baron Cowley, and his son, Henry Richard Charles Wellesley, first Earl and second Baron Cowley, during their diplomatic careers, and relating particularly to Austria, France, Spain and Turkey. There are also some papers of Col the Hon Frederick Wellesley as military attaché in Russia and miscellaneous material collected by him for his published works. The records constitute Public Record Office group Foreign Office class 519 (PRO FO 519) and are part of the Private Collections which consist for the most part of the semi-official papers, presented to the Foreign Office, of persons formerly engaged in the Diplomatic Service.