Miranda Seymour in The Telegraph:
In June 1857, following a series of seemingly unrelated uprisings by disaffected Indian soldiers in the employ of their British overlords, Cawnpore was still under siege and Delhi had been taken by the mutineers. Up in the Punjab, one of the most ferocious of the British Generals, John Nicholson, had frightened potential rebels into subjection by blasting 40 live mutineers out of the mouths of loaded cannons, before marching his modest force of 600 cavalry and 2,400 infantry down the Grand Trunk Road to the rescue of Delhi.
Theo Metcalfe, one of the closely linked tribe of ancestors around whom Ferdinand Mount builds his enthralling account of India under a century of British rule, had narrowly escaped being massacred in Delhi before, breathing fire and baying for blood, he joined Nicholson's avenging army. The self-styled Delhi Field Force were taking a brief afternoon rest when a tiny severed foot was delivered into their camp. The foot, still neatly buttoned into its shoe, was that of a small white child. Nobody knew who had brought it, but nine local villagers, following the evening parade, were hanged in savage retaliation from a single tree.Nicholson and Metcalfe were united by their fury against the natives whom they had already begun to slaughter with incontinent zeal. What neither man fully grasped was the real significance of that curious token. What it indicated, Mount suggests, was an unequivocal determination on the part of the so-called mutineers to exterminate an alien and conquering race. Mincing no words, Mount describes the chief intention of the Indian Mutiny (or First War of Independence, as it's known in India) as British genocide.
More here.