Despite being announced in the April 1983 "Dragon" catalogue as a spaceship game, and then in October 1983 's Compendium 1 as an SF role playing game, Warhammer 40,000 (Rogue Trader) was launched in September 1987, following a teaser in August's White Dwarf 92. The popularity of the game and miniatures initially surprised GW, but it went on to be their best selling system.
The original miniatures release had been the C100 Space Marines in August 1986 which had not referenced 40,000 or Rogue Trader. The first "Warhammer 40,000 (Rogue Trader)" miniatures are shown on the March 1987 Flyer. The first armies appeared on the September 1987 Flyer / White Dwarf 93.
The miniatures went through several coding changes from 1987 through 1989, making classifying them more than problematic. The initial releases were coded RTOn, which was expanded to RTNnn, where N mostly indicated the army. In May 1988, all codes were revised as part of the 1988 catalogue reorganization, and Rogue Trader became 4Nnn with a 2 digit suffix for the individual model. Unfortunately RT codes continued appearing in White Dwarf for a bit longer. For some reason the Orks disappeared from the catalogues for the next couple of years. A further reorganization in July 1989 adopted the eight digit 07nnnnxx system shown in the 1991 catalogues.