Excerpt from The Dead Duke, His Secret Wife, and the Missing Corpse by Piu Marie Eatwell, plus links to reviews, author biography & more

Nobody knew why the 5th Duke had lived the extraordinary life that he had led, or the cause of his extreme shyness and withdrawal from the world. It was known for him to disappear, for months at a time, in his network of underground warrens. It was true that he did suffer from a mysterious skin complaint, a disfiguring condition that was possibly one reason for his retirement from public view. Some spoke of madness inherited from his mother Henrietta (modern psychological analysis might point to a form of autism). Others said his desire to hide away was in some way connected with the sudden death of his younger brother, Lord George Bentinck.

A marked contrast to his introverted elder brother, Lord George had been a flamboyant figure in public life and politics. He had been both a notable racehorse owner, and prominent supporter of the Conservative politician, Benjamin Disraeli. Disraeli had been engaged, during the 1840s, in a battle with the then prime minister, Sir Robert Peel, over the controversial proposed repeal of the protectionist Corn Laws. It was due to the campaigning of Lord George that a large number of peers were persuaded to oppose Peel, winning the support of country gentlemen who would otherwise have been deeply suspicious of Disraeli – an Anglicized Sephardic Jew and novelist-turned-politician. Lord George's untimely death at the age of forty-six in September 1848 – officially from a heart attack in a field near Welbeck on his way to a dinner at a neighbouring estate – had long been the subject of colourful rumour. There were those who speculated that his involvement in horseracing had led to a quarrel with William Palmer, also known as the 'Rugeley Poisoner', and that he was poisoned by Palmer as a result. Palmer was a doctor who poisoned a number of victims with strychnine in the 1840s and 1850s, for their insurance policies and to feed his gambling habit. The idea that he had murdered Lord George was fanciful to say the least, but the whispers circulated even among the highest circles.

Even more persistent, however, was the rumour that the 5th Duke, then the Marquess of Titchfield, was somehow involved in his younger brother's death. The rumour was fuelled by whispers that the Marquess of Titchfield had been at or near the scene of Lord George's collapse. The exact whereabouts of the marquess at the time of his brother's death was never definitively established, and several eye-witnesses at the inquest testified that he might have been present at the time and place where Lord George died. A labourer named John Evans, his son and a woodman named John Mee, all said that they saw someone at the spot, and that they thought it was the Marquess of Titchfield.

Madness, guilt, eccentricity, subterfuge: whatever lay behind the 5th Duke's peculiar behaviour, the person least likely to know the truth of the matter was his successor William, the 6th Duke. William had never met his eccentric forebear in life, and only set eyes on him when he was called to see the 5th Duke's body laid out after his death. The new duke was perfectly content to accept his distant cousin's behaviour as a harmless, if expensive, eccentricity: a peculiar fetish for burrowing which any Englishman was entitled to indulge in his own home, if he had the means and inclination to do so. The 6th Duke had the reputation, among his contemporaries, of being a 'good fellow' – a phrase that, at the time, carried with it a specific set of connotations. Like most men of his class and generation, he asked few questions and simply got on with the job of settling into his strange new home, transforming its echoing underground vaults into buzzing reception rooms and ballrooms to entertain the highest of high society. Under William's regime, the old house crept out of the shadows: Welbeck Abbey began to look less like a building site and more like a stately home.

Excerpted from The Dead Duke, His Secret Wife, and the Missing Corpse by Piu Marie Eatwell. Copyright © 2015 by Piu Marie Eatwell. Excerpted by permission of Liveright / WW Norton. All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.