Reporting to chief executive Sly Bailey, Watson is to take direct responsibility for MGN's three principal commercial functions: advertising, circulation and marketing. He will also be a member of the executive committee of the group.
He joins from 'Who Wants to Be a Millionaire?' firm Celador International, where he was managing director.
However, it was his role at News International that Watson is best known for -- he was marketing director for News Group, which publishes The Sun and News of the World. He also headed up News International's short-lived Currant Bun ISP, which later became The Bun.
He joins after a number of senior executives have been axed at Trinity Mirror, following Bailey's appointment as chief executive.
Last month saw the group's marketing director Alisdair Luxmoore go. He was replaced by another former News International stalwart Trinity Mirror editorial director Phil Hall, who was the former editor of the News of the World. Watson and Hall were contemporaries at News International.
Luxmoore's exit came as the Daily Mirror's circulation dropped below the critical 2m mark for the first time, falling to 1,997,846 with March's ABCs. The just-out April ABCs show a further fall as sales dropped to 1.92m. Watson will be tasked with turning this situation around after the newspaper's costly anti-war stance.
Luxmoore was the fourth senior Trinity Mirror executive to lose their job this year. The other departures were Mark Haysom, managing director of Trinity Mirror's national newspapers, Richard Wyatt, director of corporate development, and Joe Sinyor, chief executive of newspapers, in January.
Ellis will take up his new role on June 5 2003 and his appointment will not affect the editors of MGN's national newspapers -- Daily Mirror, Sunday Mirror and The People who will continue to report to Sly Bailey.
According to Bailey: "The new role is at the heart of an improved management structure for our national newspapers. Ellis has enormous commercial experience in media and, in particular, national newspapers. He will bring a renewed commercial focus and vigour to the operation. I am delighted to welcome Ellis to our team."
Watson joined Celador in 2000 as its head of digital after helping to found internet venture Talkcast with former Times marketing director Toby Constantine.
Talkcast offered digital messaging and news information services tailored to individual consumers, but foundered like many dotcom startups.
He quit News International in May 1999 to become general manager of The Sun's free internet service provider, Currantbun.com.
Watson, who joined News International in 1994, left after five colourful years. The larger-than-life marketer built a reputation in the industry, where he became known as the Kelvin MacKenzie of newspaper marketing, partly because of his trademark style, which involved colourful invective.
At the time of his departure from NI, it was reported that Watson was "uncomfortable" with the appointment of Alisdair MacLeod as the managing director of News International Digital Publishing. MacLeod is the son-in-law of NI's chairman, Rupert Murdoch.
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