Bardock was born on planet Vegeta. Planet Vegeta has been passed down, father-to-son, for many generations. It was now in the hands of Vegeta's grandfather (King Vegeta's dad). When Bardock was born, he had a power level of 150. Usually when babies were born on planet Vegeta, they're power levels were around 50 or so. They expected him to be a great warrior.
Bardock's dad ( Goku's grandfather) was really hard on his son, as was every saiyan. He trained every day to be a official saiyan warrior, going on missions for the king himself. Bardock didn't go to school either, being 100% dedicated to fighting. When he was 10, his father was sent off on a mission ordered by the king. There was a new pirate in space, named Cold. He had one of the biggest power levels in the universe. Bardock's dad died in a battle with Cold and his 2 unknown sons. Bardock then started to slack off, and became average just like all the other saiyans.
When Bardock turned 12, the king had also died in battle, so King Vegeta took over the throne. There was word from the other warriors that Cold and one of his sons had traveled to different galaxies, however, the other son was still in their galaxy. He had already taken over half of the galaxy, working his way up to Planet Vegeta.
When Bardock turned 24, he became a official saiyan warrior. He was working for the king himself. They found out that Cold's son's name was Freiza. He had a power level even bigger than Cold. Since Cold's sons had captured so many planets, he was now being known as "King Cold". Frieza came so close to the planet, the saiyans could fly to his spaceship. King Vegeta started worrying then.
Bardock was never married, but he did get his girlfriend pregnant. Frieza started fighting to be king for the planet. He had even recruited saiyan warriors to do his missions. King Vegeta still hadn't given up yet.
One day, Bardock got sick of King Vegeta, and went to Frieza for a mission. He also didn't get along with him. On the day his son, Kakarot (Goku), he confronted Frieza all by himself. Frieza then killed Bardock with a single ball of energy, which also destroyed Planet Vegeta. Kakarot escaped to planet earth, and the dragonball series begins.