Imperial history survives in objects.

Apart from a few raggedy stories no longer connected to their proper teller, all that survives of my father's wartime Nigerian adventure is a hammered silver box with AIKINIMADUKANO hand-punched on the bottom to announce that a man from Kano made it; that, and a pair of sightless Ibo heads, presumably male and female, who stand in my mind for the juicier oppositions of colonial fantasy. These from a time before Boko Haram and before Biafra, when Lagos was still the capital and Guinness exclusively licensed there.

Two similar objects spark off Ferdinand Mount's 700-page slice of Indian history: also ebony, now tuskless, but large enough for a child to ride on. The Mount elephants, and great-aunt Ursie, are the most visible remains of a family connection to India that goes back to Trafalgar year and, like most family stories connected to the Raj, continues almost obsessively and unthinkingly for a century. One can assume that the British India marque was stamped on Ursie's bottom if such a remote place could ever have been inspected, but it remains inviolate because the Mount ancestry is so richly storied, with Lows, Shakespears and Thackerays (the second unconnected to the playwright, the third absolutely connected to the novelist, who was born in India in 1811) all involved with one another and with the administration, trade and military domination of the subcontinent.

The Lows hail from Clatto in Fife, which is why the young and coming David Wilkie was commissioned to paint a portrait of John Low, the main unifying figure of the first half of The Tears Of The Rajas, and possibly also of Captain Robert Low, who came back from the east to build Clatto and establish a dynasty. Mount does not, Zelig-like, put his family, let alone John Low himself, at the centre of every major event in the slow, bloody conquest of India, but he and they are always there or thereabouts. Sometimes they are at the heart of the fighting, sometimes injured and on the sidelines, sometimes distracted momentarily by private griefs, as when John and Augusta (née Shakespear) lose two baby girls in succession to the climate, a story so common as to be commonplace, until real and sympathetic faces and voices are put to it.

Imperial history also survives in metaphors, now that it is scarcely taught at all, or only in an apologetically revisionist and correct way. A friend's daughter, recently graduated in British history, didn't respond at all to the name of Warren Hastings, but pounced on my sarcastic follow-up, which was that she might have heard of Warren Beatty instead; she did, however, have clear theories on the evils of colonialism.

The great Indian metaphor remains that of the Jewel in the Crown. Like any diadem, it is profoundly impressive from a distance. But take a jeweller's loupe to it and the flaws, fractures and tiny imperfections start to become visible. Mount reports that during his family's time in India, there were some 110 reported risings and mutinies, which presumably excludes those which were too small, too minor or too remote to be reported.

Whereas the great Mutiny, with its clearly drawn lines, stark opposition of British rationalism and native 'superstition', is widely known, few of the others have survived into modern memory, and certainly not the so-called White Mutiny, three years later, when 90% of the 1,300 officers in the Madras Presidency refused to obey orders from senior staff. The earlier massacre at Vellore in 1806 had shown appalling violence on both sides. When British control was re-established, the rebelling sepoys were rounded into a tactlessly built fives (handball) court and killed with canister shot; the other favoured retribution was "blowing away from the guns", where the perpetrator/victim was tied to the mouth of a cannon and scattered to the winds, showering spectators with quick-drying gut, blood and brain matter. The first action seen by John Low's battalion was a firing squad, hardly heroic.

Mostly, though, the tale Mount tells is compounded more of guile and compromise, politics and commerce, with violence reserved for extremity and often for use against rival imperial powers, as in the brief conquest of Java from the Dutch (and from its rightful owners). Mount's stories, piled up with details of disease, debt, hill-station convalescences and flirtations, consistently reach behind the consensus versions to create a dynamic picture of British India in the making and one that spreads nobility and shame with a convincingly even hand. The deposition of the boy-king of Oudh hardly ranks as a great moment in our national narrative, made up as the story is of patronising assumption and a big stick always in reserve, but the 'Indians' don't come out of it particularly well, either. Likewise the invasion of Afghanistan, the most vivid illustration there is that those who forget history are condemned to repeat it, and right up to date.

Mount's greatest resource here is an almost unbelievably good cast of characters, a great many of them Scots. John Low himself is a bit like Stendhal's Julien Sorel, a relatively minor character and often unwitting part of a big story that can only emerge retrospectively. But what giants surround him. The almost laughably fierce Rollo Gillespie, the cultured, complex Mountstuart Elphinstone, the preposterous but also impressive Lord Minto, who was determined not to be a Sorel but to be at the absolute heart of (read: safe distance from) the action.

And on the Indian side, with Tipu Sultan long dead and his death superstitiously confirmed many times over, there is the Peshwa, caught on the brink of slipping sighingly out of history altogether, or Nasur-ud-din, a virtual caricature of a playboy prince. The one thing refreshingly lacking from the whole panorama is the usually insistent and overpowering smell of sex, which seems a defining aspect of the Indian narrative right up to the current and steamy Indian Summers, where even the vegetation, let alone the sexual manners, is wrong. The 'dishonouring' of European women, a main plank of colonial racism, seems to have been rare; courtesy, much commoner.

The story has an inevitable dying fall, and in some respects loses its momentum (and its most compelling characters) from the mid-point on. India remained a British fixity, even in decline. Long after, when Churchill gave up India, Enoch Powell beat his breast passionately and said "It hurts, it hurts". What's left is objects and stories that harden into myth. Mount returns to the ebony elephants which he bestrode in childhood. They somehow stand for the whole imperial narrative and for a certain, rather sympathetic self-understanding that runs through this extraordinary century, in which so much British talent, intelligence, ambition, success and failure was translated into alien terms and acted out on a landscape utterly different from the parks and farms and chilly vistas of Fife. "Perhaps the British unconsciously identified themselves with the huge animals that were so essential to them both in peace and war. For the British, too, seemed clumsy in their strength and would lash out when they were maddened." Even tuskless and reduced, those wooden beasts are our history.