THE Commonwealth Games may not officially start until tonight, but the first gold medal has already been awarded - to a writer.

Australian novelist Kate Grenville last night won the £10,000 ($A23,500) Commonwealth Writers' Prize for The Secret River. Guyanese academic and poet Mark McWatt won the £3000 best first-book prize for his Suspended Sentences: Fictions of Atonement. The awards were presented by Prince Edward at the State Library of Victoria.

The Secret River deals with encounters between early settlers on the Hawkesbury River and the local Aborigines. The main character, William Thornhill, a transported convict based on one of Grenville's antecedents, takes possession of land for his family, with dire consequences.

The book marked the entry of novelists into the so-called history wars that flared a few years ago around the documentation and interpretation of frontier violence in the early days of white settlement.

"There needs to be a debate, a multi-pronged debate about what happened and how we should respond. These are complicated issues," the Sydney-based novelist said.

She was inspired to write the book after visiting her 19th-century relative's home on the banks of the river and realising that it was like a fortress.

"The book came from an area of uncertainty in the family history that gave the question of what right white Australians have to be here a personal edge. I have a nice life here because of what my great-great-great-grandfather did. I don't feel guilt but I feel a 'sorryness' in the sense that Aborigines use the term," she said.

"I am sad about what happened. Personally, I need to try to find out and open up the whole area. But I never dreamt that what was an urgent need for me was also for other people out there." There was no lesson in the book, "except that what is needed is dialogue and learning. I learned so much about the history of my country in the writing of it."

When The Secret River was published last July, The Age described it as "a powerful, highly credible account of how a limited man of good instincts becomes involved in enormity and atrocity. It is, at one remove, a sane and moving allegory of Australian development - it is also a subtle expression in fictional terms of the myth of collective guilt for the fate of the Aborigines."

Grenville says she has been expecting some critical backlash to the novel. In his new collection of essays, Sense and Nonsense in Australian History, La Trobe University historian John Hirst accuses her of embracing a "liberal fantasy" and giving Thornhill anachronistic sensitivities. Australian National University historian Mark McKenna, author of Looking for Blackfella's Point: An Australian History of Place, has lamented the rise of the novelist as historian. But otherwise, Grenville says, there "have been odd silences from parts of the media".

The Secret River has recently been published in Canada and Britain and will appear next month in the US. In Britain, where it has received enthusiastic reviews, The Guardian newspaper called it "an outstanding study of cultures in collision". Grenville says that it is ironic that although the book is very localised, it is striking a chord overseas. "Most people have anxieties about who belongs where," she said.