The tour opener against England on 27 May is followed by assignments against Ireland in Gloucester and Wales at the Millennium Stadium.
The Barbarians defeated all three countries in their most recent fixtures against them.
Latest additions to the squad announced today include New Zealand's most-capped full-back Mils Muliaina, South Africa's World Cup winning captain John Smit, Argentine points' machine Felipe Contepomi and supercharged Leinster utility back Isa Nacewa.
Among the Barbarian debutants behind the scrum are Samoan duo Sailosi Tagicakibau and Eliota Fuimaono-Sapolu and a home nations' trio of Mike Tindall, Stephen Jones and Rory Lawson.
Shane Williams is set to take his final curtain on the international stage when the Barbarians face Wales on 2 June.
In an experienced pack Duncan Jones, John Afoa, John Beattie, Juan Manuel Leguizamon and Mick O'Driscoll also become Baa-Baas for the first time.
The squad, which will be coached by All Blacks' legend John Kirwan assisted by Grant Doorey, assembles in London on 22 May.
Barbarians' squad:
Backs - Isa Nacewa (Fiji), Mils Muliaina (New Zealand), Ian Balshaw (England), Cedric Heymans (France), Shane Williams (Wales), Paul Sackey (England), Sailosi Tagicakibau (Samoa), Eliota Fuimaono-Sapolu (Samoa), Mike Tindall (England), Damien Traille (France), Felipe Contepomi (Argentine), Stephen Donald (New Zealand), Stephen Jones (Wales), Rory Lawson (Scotland), Jerome Fillol (France)
Forwards - Schalk Brits (South Africa), Benoit August (France), John Smit (South Africa), Aled de Malmanche (New Zealand), John Afoa (New Zealand), Duncan Jones (Wales), B J Botha (South Africa), Neemia Tialata (New Zealand), Jerome Thion (France), Mick O'Driscoll (Ireland), Anton van Zyl (South Africa), Pelu Taele (Samoa), Raphael Lakafia (France), Antoine Burban (France), Akupusi Qera (Fiji), John Beattie (Scotland), Pedrie Wannenburg (South Africa), Juan Manuel Leguizamon (Argentine)
Fixtures:
Sunday 27 May v England (Twickenham) 2.30pm
Tickets from www.ticketmaster.co.uk
Tuesday 29 May v Ireland (Kingsholm, Gloucester) 7.45pm
Tickets from www.gloucesterrugby.co.uk
Saturday 2 June v Wales (Millennium Stadium) 2.00pm
Tickets from www.ticketmaster.co.uk
