Sir William Stuart, KCMG, CB (3 March 1824 – 1 April 1896) was a British diplomat who served as Minister to Argentina, Greece and The Netherlands.
His older brother was Charles Stuart, 12th Lord Blantyre who married Evelyn, the second daughter of George Sutherland-Leveson-Gower, 2nd Duke of Sutherland.
[4] In 1856 Stuart began a series of posts as Secretary of Legation, first at Rio de Janeiro,[5] then at Naples from 1859 until February 1861 when King Francis II was overthrown and the British legation at Naples was closed.
[9] In 1868 Stuart was appointed Minister to the Argentine Republic,[10] although in March 1871 he was in London acting as Protocolist to a conference on the European Commission of the Danube, when he was awarded the CB.
[14] His duties there included negotiation of a bilateral treaty between Great Britain and Luxembourg on the extradition of criminals in 1880[15] (superseded by later European conventions, currently the European Arrest Warrant), and the North Sea Fisheries Convention of 1882.