The world's third-largest retailer has brought in Alan Parker's international powerhouse, parting company with Maitland after 12 years.
It is understood the switch reflects Tesco's increasing focus on growth outside of its UK heartland, despite recent setbacks in the US.
Group executive director (corporate and legal) Lucy Neville-Rolfe thanked Angus Maitland for his 'wise guidance' over more than a decade, but added: 'Brunswick, with its leading reputation and international reach, is ideally positioned to help Tesco in the next stage of its development.'
With stores in 14 countries including eastern Europe and the Far East, Tesco considers international business to be an increasingly important profit-driver.
However, 12 stores in the US have closed this year as a result of losses, amid criticism that the giant has not properly understood the market or the communities it was serving.
As part of its global strategy, Tesco has also created a new comms director post dedicated to international business.
Ian Hutchins, previously international corporate affairs manager, has been promoted to director of the same portfolio.
The moves are also part of measures to smooth the departure of Neville-Rolfe, who is set to retire in January 2013.
Although dominating the UK grocery sector with a 30 per cent market share, Tesco issued its first UK profit warning in 20 years in January.
After struggling to gain ground over other supermarkets with its £500m 'big price drop' - dubbed the 'big price flop' by analysts - Tesco has also been rocked by the departure of its UK and Ireland CEO Richard Brasher after little more than a year in the job.