The word "vaadwaur" came to mean "fool" in ancient Talaxian, following the original Vaadwaur Supremacy's demise in the 15th century AD. (STO - "The Delta Quadrant" missions: "All that Glitters", "Satellite Defense")
The history of the Vaadwaur is a long but fragmented past, with a mixture of war and exploration.
Vaadwaur fleets were aided by their discovery of a network of subspace corridors that spanned much of the quadrant. It took the Vaadwaur centuries to map the corridors. Dubbing them "Underspace", the Vaadwaur were quick to claim the network, and began using them to further expand their empire. With the help of the subspace corridors, the primitive Vaadwaur fleets could cross the quadrant in months instead of decades, and strike undefended worlds at their leisure. However, they never kept written records of the corridors, instead in committing them to their memory.
For nearly 900 years the Vaadwaur Empire would rule a large section of the Delta Quadrant through the use of the subspace corridors, their battle fleets appearing seemingly out of nowhere and destroying unprepared alien fleets and colonies with ease, soon followed by ground invasion and occupation of the planet. The Vaadwaur were cruel taskmasters, treating all peoples they subjugated as third class citizens within their own lands - using them as slaves and sources of free labor. They extracted resources from all conquered worlds. At their height, the Empire included more than a thousand worlds, and stretched as far as Talax and Borg space, controlling all in between. The Vaadwuar were also seen as the envy of hundreds species across the Delta Quadrant. Their population of this time was about 6 billion. (VOY episode: "Dragon's Teeth"; VOY reference: Voyager Companion; ST reference: Star Charts)
Eventually, in the year 1484, the Vaadwaur's subjects rose up against them; a subject race, the Turei, led an alliance to attack the Vaadwaur, decimating their homeworld and reducing it to an irradiated wasteland with orbital bombardment. However not all the Vaadwaur were killed, including several hundred members of a single battalion who managed to survive in stasis pods. The plan was for the battalion to awaken five years and then find a new world to start over and rebuild their empire. However, the stasis controls were damaged during the bombardment of their homeworld. Many more were also used, including one set on what would be known as Kobali Prime. However, Vaadwaur seemed to be too overconfident in their restoration - those within the creative arts, such as teachers, artists and poets were given extreme low priority and children were given higher priority so they could be given a chance to become soldiers.
Following the Vaadwaur's "apparent" annihilation, their subspace corridors were then claimed by the Turei. The Vaadwuar then became fables among the various species of the Delta Quadrant. Their name in the old Talaxian tongue became the word for "foolish", "weak-minded", "reckless", and "blind", particularly when someone allows themselves to be deceived by an enemy. The word was first used in Eldaxon's Collected Folklore, particularly in stories such as "The Demon with the Golden Voice", "The Tale of the Deadly Stranger", "The Tale of the Boy who Lost his Head", and "The Tale of the Bloody Hand". These stories described them as a phantom army that appears out of thin air, destroying entire colonies, and then vanishing in the blink of an eye. (VOY episode: "Dragon's Teeth"; VOY reference: Voyager Companion; ST reference: Star Charts; STO mission: "Dust to Dust")
In 2376, the Federation starship USS Voyager discovered the Vaadwaur's homeworld. During explorations of the devastated planet, Voyager's astrometrics officer, Seven of Nine, awakened one of the Vaadwaur battalion in stasis, a young officer named Gedrin. Persuaded by Gedrin that they would be helping a peaceful civilization to rebuild, Voyager's crew revived nearly 600 Vaadwaur troops before Neelix, a Talaxian and Voyager's ambassador uncovered the Vaadwaar's true history. Voyager's alliance with the Vaadwaar was broken when the Vaadwaur commander Gaul launched an attack on Voyager. Voyager barely escaped while the Vaadwaur and the Turei resumed their nearly millennia old conflict. Realizing that today was not the day to reclaim their lost homeworld the reawakened Vaadwaur took 53 of their vessels and used the subspace corridors to flee the battle and attempt to find a new world where they could rebuild in the hope of one day reclaiming their former glory. (VOY episode: "Dragon's Teeth")
In late 2381, the Vaadwaur joined the Kinara alliance along with several other species to gain access of Underspace and began blockading the Gateway to the First World. The Confederacy Interstellar Fleet and the Kinara became embroiled in skirmishes, and the Voth sabotaged the Federation subspace relay network in the Delta Quadrant. At some point before February 2382, the fugitive Neyser criminal Meegan McDonnell took control of Devore, Turei, Vaadwaur, and other leaders by occupying their minds with those of her fellow criminal Neysers. In late 2381, a Kinara fleet attacked the Federation starships USS Voyager and USS Demeter and their wave form allies near the Ark Planet. The CIF Twelfth Lamont led a fleet of the Confederacy Interstellar Fleet and obliterated the Kinara fleet. General Mattings subsequently invited the Federation ships to visit the First World. In February 2382, Vice Admiral Kathryn Janeway convinced the Presider of the Confederacy of the Worlds of the First Quadrant, Isorla Cin, to enter negotiations with the Kinara fleet blockading the Gateway. Skeen Rigger Meeml of the starship Lightcarrier responded to her hail, and the Confederacy learned of the Kinara's demands for the first time. The diplomatic exchange was enabled by the Federation starship USS Vesta. The Neyser-possessed commanding officer of the Devore warship Manticle, Inspector Kashyk, inserted himself into the conversation and made the extradition of Admiral Janeway a non-negotiable term for peace between the Confederacy and the Kinara. When the Confederacy declined to abide to these terms, the standoff degenerated into open battle. The battle came to a halt when Janeway agreed to be extradited. A shuttle carried her and two subordinates to the Manticle, where Kashyk and a multi-species security team took her into custody to stand trial. The Manticle departed afterwards. (VOY novels: Protectors, Acts of Contrition)
The appearance of the Vaadwaur is very distinct. Their skin color comes in all the same broad range of complexions found in Humans and the ridges on their face gives them very sharp features. They have small ridges on their chin and two horizontal ridges just above their nose. A large fin like crest runs across the center of their foreheads and gets wider as it reaches the top of their skulls. Their hair grows from around the mid-region of their skull, just where their fin ridge seems to end.
Neck ridges extend from their ears, along down along their neck and onto their shoulders where they curl in towards the center of their chest. This gives the neck ridges a cobra-like appearance overall. (VOY episode: "Dragon's Teeth")