As a young boy growing up in the planet of Alderaan, Bail was groomed to eventually represent his planet in the Republic Senate. At first he doubted the importance of being a senate but after an encounter with Finis Valorum, Bail was finally convinced that he could change the galaxy in the Senate.
Before Bail could become the Viceroy of Alderaan, there was a conflict between two of the powerful families that occupied the planet. The conflict was between the Bail Organa's family, House Organa, and House Antilles. A Jedi by the name of Jorus C'baoth mediated the conflict by making the families join together by way of marriage.
Bail Organa succeeded Senator Bail Antilles in the Republic Senate. Organa quickly made an impression on Chancellor Palpatine and they became allies. Apart from, Palpatine, Organa also forged friendly relationships with fellow senators Padme Amidala and Mon Mothma.
Organa was expected to vote in favor of the formation of a Federation Army. Because he knew that the senate would never vote in favor of using the Clone Army against the new Separatist threat Organa was one of the many who voted to give Chancellor Palpatine emergency powers.
As Palpatine's powers grew during the Clone Wars, Bail Organa started to get concerned. Bail started to make an alliance of sorts with The Jedi High Council and other senators who were also worried about the Emperor's growing powers.
During the Great Jedi Purge, Organa decided that he would try to help the few remaining Jedi. While trying to locate and save the Jedi, he located and saved Jedi Masters Yoda and Obi-Wan Kenobi.
After Yoda tried to kill Palpatine, Organa saved the Jedi Master before security could get to him. Bail and Yoda then fled to Polis Massa and form there contacted Obi-Wan Kenobi. Kenobi joined Yoda and Bail on Polis Massa after he barely defeated Anakin Skywalker who had turned to the dark side. Obi Wan Kenobi also brought with him R2-D2, C-3PO, and Padme Amidala who was pregnant with Luke and Leia and was in critical condition. Before Padme died she gave birth to twins Leia and Luke.
When the group arrived on Naboo, they discussed the fate of the newborns. Organa adopted Leia because it was impossible for him and his wife to produce an heir.
Organa also took R2-D2 and C-3PO. Bail continued to work in the Senate until his daughter, Leia eventually replaced him.