Rupert Edward Cecil Lee Guinness, 2nd Earl of Iveagh (29 March 1874 – 14 September 1967) was an Anglo-Irish businessman, politician, oarsman and philanthropist.

He served as a captain in the Royal Naval Volunteer Reserve and was the first commanding officer of HMS President (London Division RNVR), from 1903 until 1920.

In 1927 he succeeded his father as Earl of Iveagh and chairman of the family brewing business in Dublin and for thirty-five years directed its consolidation at home and its expansion abroad with the establishment of breweries in London, Nigeria and Malaya.

A keen agriculturist, he cleverly transformed the barren sandy-soiled shooting estate at Elveden in Suffolk into a productive farm by ploughing in brewers' grains over decades, thereby creating humus.

Lord Iveagh realised the land had to be made more profitable and manure would be needed and therefore, in 1932 he started to buy in dairy cattle, keeping only those that passed the TB Test.

Lord and Lady Iveagh took a keen interest in their Dairy Herds and prepared a 'family tree', which was regularly up dated, for every animal in their possession.

His only son, Arthur Onslow Edward Guinness, Viscount Elveden, was killed in action in Belgium in 1945, being an unlucky victim of a V-2 rocket strike.

For several years the Forestry Commission had coveted parts of Elveden Estate for extending Thetford Forest, but Lord Iveagh's success with farming brought a settlement in his favour in 1952.

He became involved in an argument about which was the fastest game bird in Europe, the golden plover or the grouse, and he realised that a book, published by Guinness, that supplied answers to this sort of question might prove popular.

Sir Hugh's idea became reality when the McWhirter twins, Norris and Ross, who had been running a fact-finding agency in London, were commissioned to compile what became the Guinness Book of Records.

"[5] While an undergraduate, he joined Thames Rowing Club to have a London base to train with Bill East, the 1891 English professional sculling champion.