Michael Adebolajo, 28, and Michael Adebowale, 22, both Britons of Nigerian descent, deny murdering Lee Rigby, who was hacked to death near his barracks in Woolwich, southeast London, on May 22.
The death triggered demonstrations from right-wing groups and attempted firebombings of mosques.
Adebolajo -- who has said he wants to be known in court as Mujaahid Abu Hamza -- is also accused of the attempted murder of two police officers and possessing a revolver.
The three-week trial will take place at England's Old Bailey central criminal court in London under tight security, amid fears of a repeat of tensions seen in the days and weeks following the murder.
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The first evidence in the case is not expected to be heard before tomorrow, after a 12-strong jury is selected from members of the public.
Armed police attended the scene of the bloody attack and onlookers filmed the incident and its aftermath on their mobile phones.
Under English law, stringent reporting conditions surround the case until the evidence is heard in court.