Gordon Rennie has 2 books in the Warhammer 40,000 catalogue, listed below in publication order with where each fits on the timeline.
Original summaries and chronology labels generated from the same catalog powering the atlas.
Gordon Rennie
The first novel of the Gothic War, this is a fleet-action story chronicling the opening of a massive void war as an Imperial Navy battlefleet confronts a Chaos incursion in the Gothic sector. It is one of the few 40k novels centered on capital-ship naval combat, drawing on the Battlefleet Gothic wargame setting.
000.M41 - 999.M41
era date, medium confidence
First published 2001
Gordon Rennie
The second Gothic War novel picks up the void-war campaign as the Imperial Navy presses its struggle against Chaos forces across the embattled Gothic sector. It continues the large-scale fleet engagements and naval tactics of its predecessor, tied to the Battlefleet Gothic game.
000.M41 - 999.M41
era date, medium confidence
First published 2003