When Frances Osborne first came across a ravishing photograph of her great-grandmother, Lady Idina Sackville, she was, naturally, intrigued. The true story of the five-times married and divorced Idina, a possible model for Nancy Mitford's fictional “Bolter”, had long been suppressed within the family as too disgraceful to mention. This book resulted from Osborne's determination to dispel the mystery.

Impeccably bred, rich, attractive and unfailingly elegant, Idina (the daughter of the eighth Earl De La Warr) was also intelligent and widely read, and could be practical when she so chose. So why, at 25, did she abandon Euan Wallace, the handsome and immensely wealthy husband with whom she had been much in love, and her two small sons, and run off with the first of her next four husbands to a life in Kenya that ended by being as sleazy as it was notorious?

Perhaps too much money was at the bottom of that first bolting. Idina and Euan took instant gratification so much for granted that if she had to stay in bed with flu and he wanted to go out dancing with friends, off he went without a second thought, while if he was not around to amuse her she didn't hesitate to grab the nearest man who would. Like all her friends, she consigned her children to the nursery so thoroughly that at one point in her life they were hardly real to her - certainly not as real as her own childish impulse to give her husband tit for tat.

Unfortunately, her ability to “whistle a chap off a branch”, which was said to be as unfailing as her chic, did not extend to keeping a chap captive, presumably because of her tendency to marry whoever she had gone to bed with, regardless of whether they really liked each other. What mattered to Idina was having fun now.

In those days, between the two world wars, if you were white and rich in Kenya you could have a great deal of fun, much of it serious, such as building a house that was more glamorous than anyone else's, or seeing your cattle prosper on the farm that your money had magicked out of the bush. You could also become celebrated for the parties at which your house-guests always found silk pyjamas and a bottle of whisky waiting for them on their pillows, and at which you and they could indulge every impulse, because the people you would shock were too boring to bother with, and the wilder ones were only too happy to join you in doing the shocking.

Hence the drink-sodden evenings in Happy Valley that ended with the random distribution of bedroom keys, and that soon became so scandalous. (The 1941 murder of Idina's third husband, Josslyn Hay, Earl of Erroll, didn't help.) Nowadays, murder aside, the parties seem a good deal more yucky than shocking.

As time went by, Idina's husbands became more shoddy, the parties more sordid, and after she had her daughter by Erroll it occurred to her to wonder what had become of her sons. Eventually, when they were grown men, she met them, and they both responded extremely generously to her charm, for which she was deeply and pathetically grateful. But both of them died young. The moment in this book at which Idina's native warmth and vulnerability are most touchingly evident, is when Osborne quotes the letter she wrote to her eldest son's widow on hearing of his death in 1944: “I know how he adored you & how little happiness you had together - always a turbulent unsettled life - so little peace & home happiness. I can write no more for I am crying with you...”

I guess that this book was written in the expectation that complete understanding would result in complete forgiveness, but it's a sad hope because that does not quite happen. I was left thinking: “Alas, the ugliness of those idle, greedy, thoughtless lives.”

The Bolter by Frances Osborne
Virago £18.99 pp310

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