Had she not shared the same publisher as scientist Tim Flannery, the story goes, she might never have learnt of the young First Fleet lieutenant William Dawes and the notebooks which inspired her new novel, The Lieutenant.

Speaking before a Canberra Times literary dinner at the Hyatt Hotel, Grenville said it was an extraordinary chance ''how a tiny, almost accidental thing like that can open up a whole new world to write about''.

Now based in Canberra, Grenville won the Commonwealth Writers Prize for her previous novel, The Secret River, an international best-seller with sales of 500,000, which was short-listed for the Booker Prize and translated into more than 20 languages.

It was in the middle of writing that novel that she came across a reference to Dawes in a book by Flannery which she read only because their mutual publisher ''stuck it in an envelope and sent it to me''.

Grenville said she had done her research and thought she knew it all, but ''there was this amazing, amazing couple of pages in the book that were completely new to me and that I couldn't get out of my mind.

''I was writing The Secret River but in the back of my mind I was almost impatient to get on to this other story about this extraordinary lieutenant and his relationship with the young Gadigal girl.''

The notebooks of Dawes, a studious young astronomer, record how he learned some of the language of the local Gadigal Aboriginal people, particularly through his friendship with a young girl named Patyegarang.

The present-day significance of that relationship was brought home to Grenville earlier this year as she was writing The Lieutenant.

''I stood on the lawn of Parliament House and [Prime Minister] Rudd delivered his magnificent apology for the Stolen Generations and I thought, 'This is terrific; for the first time in 200-odd years there is now a possibility of a conversation happening between indigenous and non-indigenous ...'

''And I thought this is exactly what The Lieutenant is about; about a man and a woman who had that conversation, 200 years ago right at the very beginning of European settlement.''

Grenville is now researching her next book, which is about the first settlers born in Australia and draws on family stories about her great-great-grandmother.

''They tell a most amazing story, so I'm going to try and tell it. The other reason I'm interested is that women are absolutely lost in the history, particularly if they were not literate, which my great-great-grandmother wasn't; they simply disappear from history and it's a real challenge to try to haul them back from oblivion and tell something of their story.''