Saturn Returns: Book One of Astropolis - Sean Williams

When former mercenary commander, Imre Bergamasc, is resurrected in the 879th Millennium, he finds that things have changed during the 150,000 years he was dead. Following a galaxy-wide disaster known as the Slow Wave, the Continuum has collapsed, the bright galactic empire reduced to millions of disparate systems in various states of disarray. Reunited with his old teammates - or, at least, reasonable facsimiles thereof - Imre must piece together both the fragments of his memory and the story of civilisation's fall. But the more he digs the more suspicion dawns that the two issues are far from separate. Was the Imre Bergamasc he no longer remembers an unwitting pawn in the fall of civilisation? Or was he, in fact, the architect?