Very tall and burly, Baron Erroll of Hale, who has died aged 86, was among the most successful and popular engineer-politician-industrialists of his generation. Although he reached his political peak under Harold Macmillan, as president of the Board of Trade (1961-63), he thought he did better as minister for power (1963-64), to which post Sir Alec Douglas-Home demoted him. There, he rushed through the Continental Shelf Bill to allow the oil companies speedily to explore the North Sea and thus "dish Labour".
When the Tories were defeated in 1964, he was rewarded with a hereditary barony. After that, he led the Tories in little-reported Lords economic, industrial and foreign trade debates. Last year he was one of the 92 elected by fellow hereditaries to survive as life peers in the transitional House of Lords.
Outside politics, Erroll was an even greater success as an industrialist. He was chairman of Bowater, Consolidated Gold Fields and Whessoe and a leading figure in the CBI, the Institute of Directors and the London Chamber of Commerce. He led successful trade delegations to south-east Asia and Latin America, and penetrated the Iron Curtain, meeting Nikita Krushchev and Chou En-lai.
A complex background enabled Erroll to bridge the class gap. Born in London, he was the son of mechanical engineer George Erroll, who had come south from Glasgow and shed his German-sounding name of Bergmans. Earlier family roots were in Rotterdam. Freddy's father also managed to send him to Oundle. After that, in 1931, he was apprenticed at Metropolitan-Vickers, then an engineering giant in the Manchester suburbs. His public schoolboy polish helped him become chairman of the largely leftwing apprentices association, and he obtained a mechanical sciences degree at Trinity College, Cambridge.
Already in the Territorials, he was commissioned in the 4th County of London Yeomanry at the outbreak of war in 1939, transferring to the tank division of the Ministry of Supply in 1940. He wound up a full colonel in Mountbatten's Southeast Asia Command, as technical adviser on armoured fighting vehicles, and took part in SEAC's first amphibious operations.
Labour's 1945 tidal wave did not touch him as the safe Tory candidate for Altrincham and Sale, and, once in the Commons, he became a militant voice for business and Tory virtues, attacking nationalisation and food subsidies. He also wanted better pay for industrial brains, so that senior executives could think in the evenings rather than wash dishes.
Having turned down previous offers after the Tories' comeback in 1951 in favour of more remunerative directorships, Erroll's first ministerial job was as parliamentary secretary for supply in Eden's 1955 government, and he held the same rank at the Board of Trade (1956-58), before becoming economic secretary to the Treasury (1958-59). Transferred to the Board of Trade under Reginald Maudling in 1959, he took over command in 1961. He survived Macmillan's 1962 purge, but did not shine, mainly because he was caught in the Tory party struggle between big business and smaller entrepreneurs.
Sir Alec Douglas-Home made him minister for power, although Erroll had conspired with Enoch Powell and Iain Macleod to block Home's selection as leader by the Tory inner circle. After the 1964 Tory defeat, Erroll, who had been warned by his doctor to take things easy, turned over his safe seat to Anthony Barber.
After his recovery, he was much sought after by big business. As chairman of Bowater's, the paper giant, he battled with Harold Wilson over his industries bill. As chairman of Consolidated Gold Fields, he fought off takeover attempts by South African billionaire Harry Oppenheimer. As chairman of a Home Office committee (1970-72), he urged more flexible licensing hours and a lower drinking age of 17.
He never lost his sense of humour; until the end, editors loved to reproduce his brief, jokey letters, usually in answer to others' gripes.
He married Elizabeth Barrow in 1950. Since there were no children, the barony lapses.