This memoir from Sir Richard Needham, 6th Earl of Kilmorey, businessman and former Northern Ireland minister, has a frank opening: ‘I came from a family of barely solvent aristocrats, who distrusted trade and despised politics. For some inexplicable reason, however, I had always been fascinated by both.’ Although generations of Needhams before him had ‘uneventful’ military careers, at 15 Richard decided upon an alternative plan: ‘I would first make some money, and then enter politics and change the world.’ What follows is the tale of how that scheme played out.

The literary quality of political diaries can be hit and miss; but Needham is a skilled storyteller, who can deftly sketch a character or situation in a few pithy phrases. He is fond but unsparing of his parents, for example, who were grand but hopeless with money. His father was of ‘the gently indolent variety of Needhams’, selling off the title’s Northern Irish house and acres for £100,000 and a pillowcase full of heirlooms, while his stylish mother ‘occasionally liked the boys and the booze more than was sensible’.

Ejection from the family nest came early, after which the author’s rather lonely childhood was patrolled by a regiment of minor and major scholastic monsters, each flaunting distinctive oddities. Take his parents’ friends, Major John and Betty Maxfield, who ran the school in Eastbourne to which he was dispatched, aged six. Major John had a tin leg, having lost his original one while in the Marines, and although ‘great fun when sober’ often had a ‘vile temper, backed up by a ruler’.

Worse awaited at Eton in 1955, a coldly savage landscape mined with sexually charged bullying and the threat of ritualised beatings from masters and bigger boys. Eton is no doubt awash with therapy and beanbags now, but back then it sounds like a plausible vision of hell, at least for many of the younger pupils. Occasionally Needham’s outrage seeps through matter-of-fact prose. Thrashings, or ‘swipings’, for poor performance or cheating were delivered with maximum drama and a birch by the headmaster, and afterwards the 11-shilling bill for the birch was sent to the boy’s parents. The killer detail lies in the dry explanation for the invoice: ‘On account of the blood, birches could only be used once.’ The repeated message from the school seems to have been that Needham wasn’t clever enough to achieve anything notable, a status belied by his future career but formalised in neckwear: ‘I left Eton with two A-levels and a tie called “The Scramblers”, which was worn by those who had done little or nothing of consequence.’

Things could only get better, and so they did. Newly installed in London, the author found himself in ‘the season’, designed to match up debutantes with eligible bachelors. He soon decided to enrich ‘the Needham bloodline’ by looking elsewhere. The quest ended with his wife Sissy, a statuesque, multilingual German blonde, who later held the fort when — as he admits — an obsession with work left his three children feeling neglected.

The business career bookended the political one, with stints at Rothmans and Dyson. But skills from business infused his political life, from MP level onwards: more practical than ideological, he believed primarily in motivating colleagues. As one of the ‘Wiltshire wets’ — his constituency was North Wiltshire — he found himself on the wrong side of Margaret Thatcher (a call to his wife in which he said ‘I wish that cow would resign’ was intercepted and leaked. Mrs T was magnanimous).

Needham holds the title of Northern Ireland’s longest-serving British minister. When he first arrived in 1983, Belfast was not looking its best, bristling with check-points and ‘pockmarked’ with bomb damage. I can vouch for this, as I was growing up there at the time. Amid an ongoing hum of IRA death threats, Needham worked energetically to make Northern Ireland a more attractive place for locals and investors. One legacy was Belfast’s CastleCourt, an enormous glass retail palace which revolutionised the city’s hitherto meagre shopping opportunities. It was spared a decisive explosion partly by the canny strategy of hiring sales assistants from Republican families in West Belfast.

Looking back at 20th-century Irish history in a short but vigorous burst of opprobium, he singles out four figures as particularly malign: Gerry Adams and Ian Paisley come in for a hammering, which they no doubt deserve, but Éamon de Valera and Edward Carson would benefit from a more nuanced evaluation. (Certainly, if the shortcomings of post-partition Northern Ireland are under discussion, the greater blame should fall on its prime minister, James Craig.)

There is enough intrigue and indiscretion here from the Thatcher and Major years to satisfy politics wonks. But I found the book most enjoyable as a slice of social history: a pungent immersion in an era during which everyone smoked, air travel was fun and alcohol was a powerful professional lubricant. The formerly cracking pace falls off a bit in later dispatches from the business arena. Yet this remains a witty and illuminating portrait, not only of one man’s career, but also of slowly vanishing worlds.