"[6] Rodd entered the British Diplomatic Service in 1883, and served in minor positions at embassies in Berlin, Rome, Athens and Paris.
He played an important part in negotiating the Anglo-Ethiopian Treaty of 1897 with Emperor Menelik II of Ethiopia.
He played an active and neutral part in the dissolution of the union between Norway and Sweden, for which he was rewarded the Grand Cross of the Order of the Polar Star by King Oscar II.
He remained in this post until 1919, and played a key role in securing Italy's adhesion to the Triple Entente.
Rodd left the Diplomatic Service in 1919, but nonetheless served on the mission to Egypt in 1920, with The Viscount Milner.
[15] He was appointed to the Privy Council in 1908 and in 1933 he was raised to the peerage as Baron Rennell, of Rodd in the County of Hereford.
[16] On 27 October 1894, Rennell Rodd was married to Lilias Georgina Guthrie (1864–1951) at St George's Hanover Square Church.
[17] He was succeeded in the barony by his second, but eldest surviving, son Francis, who later served as president of the Royal Geographical Society.