The vast library of the late Richard Adams, which ranges from a rare copy of Milton’s epic poem Lycidas to a first edition of Jane Austen’s Emma, is to be sold at auction next month.

Running to thousands of books, the Watership Down author’s collection includes a rare copy of the Shakespeare Second Folio of 1632, Boswell’s Life of Johnson and a Bible that once belonged to Charles II. Adams, who died last year aged 96, also owned a host of first editions by 19th-century English novelists including Austen, George Eliot, Charles Dickens and Anthony Trollope.

Dominic Winter Auctioneers, which will sell the library on 14 December, has valued Adams’s complete set of Austen first editions at between £60,000 and £80,000. Emma, said the auction house, was Adams’s favourite; he first read it aged 22, when he was in the army, writing in his autobiography: “It was like a revelation … I was glued to it a few hours later, when my posting came through [to Jerusalem] … It didn’t much matter to me where I was posted, as long as I could go on reading Emma.” According to the auction house, it was one of the very last books he read before he died.

The Lycidas is valued by Dominic Winter at £50,000 to £70,000, and the Second Folio at £40,000 to £60,000, with other highlights of the collection including a copy of Lord of the Flies inscribed by William Golding to Adams – the authors played correspondence chess together – and one of Laurie Lee’s Cider With Rosie, which Lee inscribed to “Richard Adams spell binder extraordinaire”. It also features Adams’s copies of The Wind in the Willows and his set of Winnie-the-Pooh first editions, books which Susanna Winters at the auction house said had a direct influence on the writing of Watership Down.

From AA Milne, Adams said he learnt “the vital importance, as protagonists, of a group of clearly portrayed, contrasting but reciprocal characters … though I wouldn’t claim that Hazel, Fiver and Co come anywhere near Pooh and his friends”. He also included a quote from The Wind in the Willows at the start of a chapter of Watership Down: “Never in his life had he seen a river before – this sleek, sinuous, full-bodied animal … All was ashake and a-shiver – glints and gleams and sparkles, rustle and swirl, chatter and bubble.”

“The reaction of a simple creature – or a child – on first seeing a true river has already been unforgettably expressed by Kenneth Grahame … I certainly felt everything that the Mole felt and was carried away with delight as I held my father’s hand across the plank bridge,” Adams wrote in his autobiography The Day Gone By. That book also revealed how “before I was eight, I had become a passionate reader”, with the author adding: “Reading was highly reassuring. It was the perfect escape – into other worlds that often seemed more valid and valuable than the real one.”

Adams’s daughter, Juliet Johnson, writes in an essay for Dominic Winter: “Some of the first things he read were poems by Thomas Hardy, Treasure Island, much of Charles Dickens, and Harriet Beecher Stowe’s Uncle Tom’s Cabin, a book that distressed him terribly and cast a long shadow forward to the evil slave trader Genshed in his own novel Shardik.

“With his undergraduate studies interrupted by war, he found the works of Jane Austen, and particularly Emma, a solace and mainstay – as did thousands of soldiers both before and after him. And so it went on all his life. To Richard, books were a consolation that broadened your horizons, told you truths about things most people in your life would brush under the carpet or have no experience of, and comfort you when things were bleak.”

When she and her sister were children, Johnson said, Adams would read to them constantly, everything from Moonfleet to Paradise Lost, Puck of Pook’s Hill to Hamlet. “He never quite succeeded in imparting to us his own overpowering love of poetry – and when I became a teenager, his overemotional poetry reading was embarrassing and made me uncomfortable – but we shared his love of novels, and generally responded enthusiastically to these,” she said.

Johnson added that when Adams found success as a writer – he was 52 when he wrote Watership Down, which went on to win the Carnegie medal – he could “at last afford to indulge himself and become a true bibliophile. Much of what he collected remained unknown to us until we found it on the shelves after his death. I think it is fair to say we had no idea he had so much. Collecting became almost an obsession,” she said.

Winters at the auction house said that Adams’s collection was “a proper library – not just one to be looked at … There wasn’t a special place for the more valuable books – they weren’t under lock and key, they were there to be enjoyed. I was amazed when I first walked in.”