The anniversary of the start of the First World War has special significance for one Surrey man, whose father lived the true story behind the Hollywood film War Horse.

Robert Mackay's father Tom Mackay was a member of the Canadian contingent of the British Cavalry Brigade.

Mackay has written a novel, Soldier of the Horse, based on his dad's experiences. He spoke with Stephen Quinn on CBC Radio's The Early Edition:

Does [the film War Horse] reflect what really happened, according to what you have learned from your father?

There are some parts that are definitely realistic and accurate.

In particular, I got a real kick out of the cavalry charge, which is just how I imagined it, and how my father told it.

Did your dad talk a lot about his time in the war?

I would ask about the wounds on his legs…He eventually told me it was from gunshot wounds. And I said, 'Well, how many times were you shot?'

And he said, 'Oh, three or four.'

Robert and Tom Mackay

Robert Mackay, at left, was inspired to write a novel based on the experiences of his father, Tom Mackay, in the Canadian Cavalry Brigade. (Courtesy of the Mackay family)

Reading what is more or less an official version … one of his superior officers … recorded in his story that he had 59 bullet holes in one leg and, in the other leg, they couldn't count them.

You have visited your father's battlefields in Europe. What was it like for you?

We met a very interesting Frenchman named Jean-Paul Brunel…One day, he noticed  … what he thought was a boot. It turned out to be a Canadian named Willoughby who obviously had been lost and accidentally buried by shellfire.

He still had the two dog tags … In fact, his name is engraved on the side of the Vimy memorial.