financier and diamond magnate who rivaled Cecil Rhodes in struggling for control in the development of the South African mining industry.

The son of a Jewish shopkeeper, Isaac Isaacs, in the East End of London, Isaacs followed his brother Henry to Kimberley, Cape of Good Hope, in 1873 to seek his fortune in the diamond rush. Adopting the name Barnato Brothers, which he and his brother had used in London as vaudeville entertainers, the two formed a diamond brokerage firm in 1874. Two years later “Barney” Barnato began the bold speculation in mining claims that led to the formation of the Barnato Diamond Mining Company (1880), which seriously challenged Cecil Rhodes's De Beers Mining Company. The struggle for control of the industry resulted in Rhodes's victory and the merger of the two companies as De Beers Consolidated Mines (1888), in which Barnato was made life governor. The same year he was elected to a seat in the Cape Parliament, which he held until his death. In 1889 he resumed speculating, buying up mining claims and real estate in the newly discovered Witwatersrand goldfields and floating Barnato Consolidated Mines and Barnato Bank. In ill health, however, Barnato committed suicide by jumping from a ship bound for England.