Saiyans

Universe 7
The Saiyans are a fighting race who, since ancient times, have lived a violent and inhumane lifestyle, where they attack numerous planets to build up wealth and goods. As noted by Whis, "ancient Saiyans" possess different ki from the ones in the present time. The Original Super Saiyan appeared approximately 1,000 years prior to the Frieza Saga, approximately 238 Before Age, and is described by Vegeta as a Super Saiyan who could only retain his status in the transformed state. This Saiyan was an individual with a noble heart, and along some of his comrades, tried to stop their evil fellow Saiyans, turning into a Super Saiyan God. However, he couldn't achieve his goal and perished. In the legend, he appeared to have lost control and gave in to his destructive primitive desires, destroying himself with his own power.

A small group of Saiyans eventually found their way to Planet Plant in Age 550, and the history of the Saiyans predating their conflict with the Tuffles, reveal the Truffles had a plan to eradicate the Saiyans. The Saiyans lived in the arid wastelands, while the Tuffles lived in great cities, employing advanced technology. Eventually the Saiyans attacked before the Truffles could elimiate them, with the intention of conquering the Tuffle's great cities and extinguish the race. This sparked a ten year long war.

After their victory over the Tuffles, the Saiyans were approached by the Arcosians (Frost Demons). These aliens had money and technology, but their planet was unsuitable, so they hired a group of Saiyans to take over a planet for them; in return, they would share their technology with them. Over the years, the Saiyans also learned how to use the Tuffles' advanced equipment and became smarter and less barbaric, although they still lusted for fighting and destruction.

★ ★ ★ ★ ★ ★ ★ Occupation by Frieza ★ ★ ★ ★ ★ ★ ★

In Universe 7, the Saiyans joined the Frieza Force when it was still under the command of King Cold, while according to Daizenshuu 7 around Age 731, about a year following the Saiyan victory over the Tuffles, the planet was conquered or annexed by Frieza's empire and the Saiyans (like many other races) were drafted to serve as soldiers in Frieza's military. Due to the Saiyans' innate strength and penchant for violence, they were considered to be useful mercenaries and assisted in the conquering of many planets, or if assignment called for, eradication of the planet's population (even Saiyan children were considered powerful enough to conquer some of the weaker planets, such as Earth).

Eventually, seeing how quickly some of the more gifted Saiyan warriors were gaining power through battle, around Age 735, Frieza grew concerned with the potential of the Saiyan race and thought that they would grow strong enough to face him or even become the fabled Super Saiyans, able to defeat him in battle. In Age 737, a Saiyan scientist develops the Saibamen using biotechnology and those creatures make their way into the Galactic Frieza Army through the Saiyans. Soon, in Age 737 as well, the maniacal warlord Frieza destroyed Planet Vegeta, nearly eradicating the Saiyan race. There were only a few thousand Saiyans on the planet. As a warrior race, it would be difficult to increase their numbers (presumably, though left unsaid, because they would war with each other over superiority). Initially it was presumed that only three pure-blood Saiyans survived the destruction: Vegeta, Nappa, and Raditz as they were not on the planet at the time. Once the three discovered that their planet was destroyed, Frieza lied to them that an asteroid had hit their world, and offered them continued employment in return for eventual wealth. Unknown to Frieza and the remaining saiyans under his command, there were other saiyans that had escaped the destruction of the planet.

Universe 6
In Universe 6, their history diverged from that of Universe 7, the Saiyans remain to be a thriving race with their original planet intact. They have also come to use their innate capacity for combat productively, fighting evil rather than causing it. Around 220 Before Age, a Legendary Saiyan appeared among the Universe 6 Saiyans.

Universe 6 Saiyans lack tails and can transform into a Super Saiyan with more ease once they obtain the knowledge of the transformation. However the Universe 6 Saiyans were unaware of the existence of the Super Saiyan transformation until they were introduced to it by the Universe 7 Saiyans in Age 779 - with Cabba being the first Saiyan of Universe 6 to achieve the form. The only transformation that the Universe 6 Saiyans were aware of was the demonic Legendary Saiyan, with a Saiyan capable of transforming into it appearing once every 1,000 years.

Universe 6 Saiyans, similar to their counterparts, were employed by the emperor of the universe, Frost, in order to fight in wars on his behalf. The two remaining Universe 7 Saiyans meet the Universe 6 Saiyan, Cabba in the Tournament of Destroyers years later after the genocide in Universe 7. The Saiyans of the twin universes came to fight in combat in the Tournament of Power. When Team Universe 6 lost in the Tournament of Power, the Saiyans were erased with the rest of Universe 6. They were later revived when the erased universes were restored.