For a man who had failed to land a job as a journalist on graduating from university, Sir Christopher Bland, who has died aged 78, was to leave an extraordinary mark as one of the big beasts of British broadcasting. He was a brisk and effective chairman, both of the BBC and London Weekend Television (LWT), and deputy chairman of the Independent Broadcasting Authority (IBA). For good measure, he was chairman of BT at the time when it was formulating its plans to get into television, and chaired the Royal Shakespeare Company.

His most remarkable achievement was to come up with an imaginative scheme binding in many of the key talents at LWT, including Melvyn Bragg and Greg Dyke, in a consortium that successfully bid to retain its franchise in 1991 and made millionaires of its participants. Bland would say that the worst day of his life occurred when LWT was taken over three years later in a hostile bid from Granada.

Christopher came from Northern Irish gentry but was born in Japan to James, a Shell engineer, and his wife, Jess (nee Brodie). A traditional expat childhood saw him at a spartan boarding school, Sedbergh, in Cumbria, going to see his parents one year in three, spending British holidays with them one year in three, and otherwise staying with relatives in the grand Saintfield House in County Down, later a location for Game of Thrones.

At school, he joined in country pursuits and was remembered as being particularly organised. Acutely conscious of his Anglo-Irish heritage, dubbing himself a member of “a lost tribe”, in later life he parlayed his family history into a novel, Ashes in the Wind (2014), and in 2016 the Jermyn Street theatre, London, staged his play, The Easter Rising and Thereafter, reflecting on the centenary of the rebellion.

During national service with the Royal Inniskilling Dragoons (1956-58), he learned to fence, and when he went to Queen’s College, Oxford, to study history (1958-61) he became captain of the university fencing team. He fenced for Ireland at the 1960 Rome Olympics. After being rejected for three journalistic jobs, including a BBC traineeship, he opted for business and became an assistant advertising manager with Currys. He then joined the sewing machine company Singer before moving into management consultancy with Booz Allen Hamilton, where he became a commanding managing director.

He became involved in Conservative politics as a chairman of the moderate Bow Group (1969-70), and edited its magazine, Crossbow. In 1967 he was elected to the Greater London council as a member for Lewisham, having been promised, he said, that he had no chance of winning, and doing so only because alphabetical order placed his name first on the ballot paper. He was chairman of the schools subcommittee of the Inner London Education Authority. One of his Conservative acquaintances, Christopher Chataway, the minister of posts, invited him to become deputy chairman of the IBA (1972-80).

At the age of 34, Bland, who did not then possess a television, launched the career in broadcasting that would define him.

Meanwhile he was building his fortune and business reputation by sorting out underperforming companies. He always carried in his wallet a photostat of the £1m cheque he received after the sale of the printers Sir Joseph Causton and Sons, in which he held a 25% share.

In the 1980s there were headlines when he reunited with Jennifer (nee May), his teenage sweetheart, by then married to Viscount Enfield (Thomas Byng). They married in 1981.

Bland’s introduction to LWT, one of the liveliest of the commercial television companies, came from its chairman, John Freeman, who met him at the IBA. Freeman recruited him to the board of LWT Holdings, where Bland succeeded him in 1984. Television operations came under a separate board, but Bland’s television understanding was honed through an invitation to sit in on the weekly programme meetings of its chairman, the vastly experienced Brian Tesler, and John Birt, the programme director.

Large and ebullient, but with a famously short attention span and an obsession with punctuality, Bland was admired for the incisive way and good humour with which he ran the board. He was brave, decisive and rigorous in preparation. One colleague said: “He never supported anything when he hadn’t interrogated his own mind. But once he had made it up, he was resolute.”

Alongside a reputation for charm he could also be startlingly rude, often to junior staff. Papers could be flung about and he ran through a number of secretaries. Apologies followed. Dyke, who became chief executive, said that the best riposte was to shout back the first time he shouted at you. A favourite Bland retort, even heard in the BBC boardroom, where his direct approach contrasted with more ruminative tradition, was: “Bollocks! Next question!” Bragg found him “feisty and aggressive” but nonetheless “someone who could provide the radical changes the company desperately needed and preserve and encourage what we were there for – trying to make good television”.

Bland streamlined LWT, cutting staff and selling off its travel, publishing and technology businesses to concentrate on television. Then he pulled off his masterstroke when the franchise was auctioned in 1991. He was up against a much wealthier bidder, but applicants had to pass a quality threshold. To keep hold of his talented team, Bland devised a scheme where the key 52 would invest in the bid with huge gains if the stock price rose dramatically. He bid low at just £7.5m, successfully gambling that the rival consortium would fail the quality test although their bid was far greater, at £36m. It was a famous success. But three years later Granada mounted a takeover bid and, after a bitter fight, in which Bland even contemplated risking his own money, Granada prevailed.

Friends said it took the highly competitive Bland a year to recover. He grew a beard, uncharacteristically raggedy. He found other jobs: chairing the National Freight Corporation, where he rationalised again, selling off Pickfords; taking huge pleasure in buying Leith’s School of Food and Wine with Caroline Waldegrave; overseeing the publishing business Canongate, run by his stepson Jamie Byng, and continuing his stint as chairman of the Hammersmith and Queen Charlotte’s hospitals, later the Hammersmith Hospitals NHS trust (1982-97). In 1993 he was knighted for his NHS work.

The government came calling and in 1996 he was appointed chairman of the BBC, where his old colleague Birt was then director general. He backed Birt’s controversial reforms, such as separating off production and integrating the World Service, as well as digital expansion. When Birt left, he brought in Dyke.

Bland left in 2001, before the controversy two years later over “unfounded allegations”, made in a report by Andrew Gilligan, about Tony Blair and Iraq, which led to the Hutton report and departure of both chairman (Gavyn Davies) and director general (Dyke). But he went public to call the sacking of Dyke a mistake and few believe that he would have allowed the situation, and relations with the government, to get so out of control.

By then, his qualities had brought him to the attention of BT, another national institution, labouring under £30bn of debt. Once again, as chairman (2001-07) Bland rationalised. A lover of lists, he set out priorities including reduction of debt, a rights issue, a new chief executive, and the sale of the mobile business – something with which he disagreed but which was a condition of his appointment. By the end of his first year debt was halved and he was ticking off the list.

However, the share price took longer to recover and Ofcom threatened to break up the company over access to its network for rival operators. Again he resolved things, rolled out broadband and found growth from new business. When he stepped down, BT had turned a corner.

Bland’s personal interests were equally varied. He was a keen fisherman and skier, and an avid reader with a particular liking for hard-boiled American crime novels. He revelled in his chairmanship of the RSC (2004-11), attending every play when the company performed the complete canon, to support the rebuilding of the Stratford-on-Avon theatre. Unusually for such projects, this was completed on time and on budget.

He enjoyed stocking the huge wine cellar in his Hampshire home and acquired a vineyard in Gascony next to his French house, where the generosity of his house parties was renowned. He supported his wife’s racehorse breeding. He even penned a second novel, Cathar (2016), claiming that he wished he had spent more time writing.

He is survived by Jennie, his son, Archie, who is a Guardian journalist, two stepsons, Jamie and William, and two stepdaughters, Georgia and Tara.

• Francis Christopher Buchan Bland, businessman, born 29 May 1938; died 28 January 2017