From March, Dawe, who currently has responsibility for marketing The Sun, The Times and The Sunday Times newspapers, will sit on the book publisher's UK executive committee and report to chief executive Victoria Barnsley.
Barnsley said marketing activities at the book publisher have "never been more strategically important" as the digital world enables more interaction directly with consumers.
She added: "We have a fabulous team of marketers here at HarperCollins and I believe the creation of this new role will allow them to develop to a new level, as we put the reader more firmly at the heart of everything we do. Barnaby comes with outstanding credentials and I am really looking forward to him joining my executive team."
HarperCollins is owned by News Corporation, parent to News International. Dawe was only appointed to his new role at News International in September (2011), reporting to Katie Vanneck-Smith, following a sales and marketing restructure.
However, Dawe pointed to the recent explosion of e-readers and tablets as proof that book publishing is going through an "extraordinary revolution" which requires the marketing of books "to see its own revolution".
He said: "Already up to 15% of sales are coming from digital in the UK, with that percentage set to grow exponentially... In joining the HarperCollins team, I relish the exciting marketing opportunities that this shift in consumer behaviour brings".
Barnaby’s previous experience includes senior positions at Turner Broadcasting, Heart FM, BSkyB and Channel Four.
Dawe was made marketing director for The Sun and News of the World in April 2010, having joined from Turner Broadcasting, where he had held the post of vice-president of marketing and communications since 2008.
Prior to Turner, Dawe had been managing director of Heart FM for two years, until Chrysalis was bought by Global. In 1997, Dawe was marketing manager for Channel 4, followed by a series of marketing roles at BSkyB, including director of marketing at Sky Networks.
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