Akira Toriyama explain how a Saiya can become Super Saiyan, Super Saiyan God legend, and how can we be as strong as the Saiya people
If you look at the story Dragon Ball technically, Goku is the first character to turn into Super Saiyan. But chronologically, it turns out that the first Saiya man who turned into Super Saiyan is not Goku, you know!
This is actually not so surprising, given that Vegeta himself once said that once in the legend there was a Saiya man who became Super Saiyan. Even so, surely we wonder, who is the first Saiya man who managed to become the Super Saiyan? Then, with the appearance of the Dragon Ball Super story, is there any connection with Super Saiyan God?
In a an interview with Akira Toriyama summarized in Saikyo Jump January 2018 edition (release on December 1, 2017), the creator explains the legend of Super Saiyan and Super Saiyan God.
At that time, Toriyama was asked: Is the legendary Super Saiyan feared by Frieza is Super Saiyan God appearing in Battle of Gods ? Here's an explanation from Toriyama:
"In a way, they're the same people (Super Saiyan first and Super Saiyan God). Long before the planet Vegeta became a planet for the Saiya people, there was a good man named Yamoshi though a Saiya.
"He and his fellow comrades started a rebellion, but he was urged and became Super Saiyan for the first time. The frightening change and style of fight makes Saiya more foggy. However, as outnumbered, Yamoshi was eventually exhausted and defeated, but this was just the beginning of his legend.
"Afterwards, the soul of Yamoshi ventured in search of six good-hearted Saiya, seeking a new savior: Super Saiyan God."
The first Super Saiyan God, Yamoshi, as described by Shenlong in the Battle of Gods