Prior to becoming a member of the Dominion the Cardassian military had never really been capable of projecting forces well beyond its own borders in sufficient numbers to seriously threaten the core worlds of the Federation or Klingon Empire. The Dreadnought project was an attempt to rectify this situation by fielding a heavy-duty aed drone weapon. This craft was to employ advanced computer technology in order to operate completely autonomously under all situations. It was to have advanced tactical analysis and response systems and would be fitted with heavy duty shielding and defensive weaponry in order to enable it to penetrate almost any standard level of defences.

Once at the programmed target Dreadnought would detonate its main warhead - a two thousand kilogram matter/antimatter device1 with a 45,000 Megaton yield. This would be used against 'high value' targets such as shipyards, starbases and planets - although Dreadnought was also technically capable of engaging ship sized targets if required.
The Dreadnought project was approved in 2364, and from the first suffered many problems. The Cardassians had intended to have the first missile ready by 2367, but a combination of technical difficulties caused many delays. These problems centred around the computer core and the warhead; the former was always going to be a highly ambitious effort for the Cardassians, who have little experience with self programmable computer systems. The warhead was also the largest the Cardassians have ever fielded, and many problems were experienced in its development. Eventually the Cardassians decided to use a kinetic detonator unit in order to overcome these problems.

The first prototype Dreadnought was finally ready in 2370. After several months of tests with a dummy warhead - nearly half of them unsuccessful - the Cardassians decided to expend the prototype in a live fire test. It was launched against a Maquis munitions facility at Alpha 441 in the Badlands1 in order to give it a combat workout while not subjecting it to a high threat environment. Unfortunately for the Cardassians, the Dreadnought vanished without trace. Assuming that it had failed in even this relatively simple mission, the Central Command ordered the project cancelled.

Had the Cardassians known the truth they would have been more than alarmed; the Dreadnought had in fact penetrated the Maquis defences but then failed to detonate. The Maquis recovered the missile and re-programmed it to attack a Cardassian shipyard on Aschelan V, but after launch the missile was swept into the Delta quadrant by the Caretaker. Dreadnought, now suffering malfunctions to several systems, subsequently locked onto Rakosa V, an inhabited system in that quadrant. USS Voyager made several attempts to stop the missile, but this time Dreadnought performed exactly up to specifications. Eventually Voyagers chief engineer managed to phaser a hole in the warp core, destroying the missile just short of its target.