AS Simon Tolkien tries to stay cool in sunny Santa Barbara it is raining over his old stomping ground in Oxford, apt considering the novelist is visiting Blackwell's next week to talk about his new wartime tale No Man's Land.

The story set during the First World War is one he has been waiting to tell for many years, inspired by his famous grandfather JRR Tolkien's harrowing experience at the Battle of the Somme.

The dramatic page-turner featuring Adam Raine, a young man repeatedly cursed by misfortune, is published next week, 100 years on from the eve of the battle when more than 60,000 troops were injured or killed.

Speaking from his home in California, where he lives with wife Tracy, daughter Anna, 14, and son Nicholas, 25, said he was looking forward to returning to Oxford where he spent his childhood.

He told The Oxford Times that the part his grandfather played in the First World War had always intrigued him, inspiring him to write his latest novel: "I was always really interested in the First World War when I was a kid," he said. "I was born in 1959 so it wasn't ancient history, and my grandfather had fought in the Somme, not that he ever spoke about it.

"I grew up in Watlington, and saw all the names on the war memorial and realised what a blow that was to such a small place.

"I knew one lady in Garsington and she lost five brothers in the First World War - which wormed its way into my imagination."

The 57-year-old added: "I was crazy about history when I was a kid. My mum gave me a recording of 1914 - the sound of shellfire."

"I went to the Dragon School in Oxford, and then to a Catholic boarding school, before reading history at Trinity, Cambridge."

But despite studying history at Cambridge he found it too dry, so instead became a barrister in London and wrote courtroom dramas, before becoming an author in 2000.

"There was nothing about what it would be like in a trench during my degree so I found it rather boring. Instead I visited the Somme in 2006 and was very moved by it.

Although his grandfather JRR Tolkien fought in the Somme and survived he never spoke about it, as was so often the case. "He did not choose to talk about it - he didn't feel it was right to share that with people at home."

But Mr Tolkien said his grandfather did communicate his feelings about the war through his writing, including The Lord of the Rings: "I read the book to both my children," he said. "You can understand how someone who experienced the Somme would have written it - there are passages that take you straight back to what the trenches were like.

"If you lived in Birmingham and Oxford and then found yourself in a trench in July 1916 it would change your imagination. It made him feel that technology was an evil and the guns slaughtering each other was where the world ended. That came out in characters like Saruman and Sauron."

He describes his grandfather staying on at Exeter College to finish his degree, after the First World War started, as an "act of hope."

"He must have known what he was facing because the war had been going on since 1914. It was impossible not to go, unless you were a coward and my grandfather was not."

Like JRR Tolkien, Adam Raine in No Man's Land wins a place at Oxford University, until the outbreak of the First World War tears everything apart, and he is forced into bloody fighting and a hailstorm of bullets.

It is not hard to see why Simon Tolkien found his grandfather's story so dramatic. When JRR Tolkien arrived as an undergraduate at Exeter College in 1911 he had no idea of the horrors that lay ahead for him and his fellow students.

In June 1915 Tolkien applied to join the Army at the Oxford recruiting office. The following month he became a second lieutenant and was appointed to the 13th Service Battalion of the Lancashire Fusiliers. In June 1916, Tolkien was shipped to France and his C Company was sent into action in the Battle of the Somme.

In July Tolkien served two five-day duties on the frontline. In October his battalion was inspected by Sir Douglas Haig, the British commander at the Battle of the Somme. Shortly afterwards, Tolkien suffered trench fever and was repatriated the following month.

In 1917 Tolkien faced a series of medical boards but was never declared fit enough to return to the frontline. Many of his contemporaries did not come back.

JRR Tolkien survived and went on to gain fame by becoming a key member of The Inklings, and writing The Hobbit and The Lord of the Rings, but he never forgot his time in the trenches.

Although they never spoke about the war, writing No Man's Land has brought Simon Tolkien even closer to his grandfather.

"I think my grandfather would have been very pleased that I wrote this book - I know my father is," he concluded.

The ex-pat, who moved from London to the United States in 2008, said he completed a great deal of research on what life was like for the Edwardian poor, and the pals battalions which were formed to fight on the Western Front, for his new novel.

As for his impending visit, Mr Tolkien added: "Since I went to California I have come to really love Oxford. Port Meadow is just so beautiful and The Perch, The Trout and Addison's Walk, and the amazing architecture.

"Now when I come back I feel like I am seeing it for the first time."

*Simon Tolkien will be talking about No Man's Land at Blackwell's on Wednesday, June 29 at 7pm with proceeds going to seAp, a service that provides help and support to veterans of all ages. This will be Simon's only UK event to promote his book. 01865 333623.