Breha Organa died in 0 BBY.
Breha Organa was a human female of Alderaan who reigned as queen of that world during the final decades of the Galactic Republic and the early years of the Empire, also serving as her planet's Minister of Education and as head of the House of Organa. Married to Senator Bail Prestor Organa, she was unable to bear a healthy child of her own — a difficult pregnancy left her dependent on a cybernetic heart — and at the end of the Clone Wars in 19 BBY she and Bail adopted the newborn daughter of Padmé Amidala and Anakin Skywalker, raising her as Princess Leia Organa. Under Palpatine's New Order, Breha quietly turned Alderaan's resources, relief missions and refugee networks toward the growing rebellion, working alongside Bail as one of the movement's founding architects while shielding Leia's true parentage and, for as long as she could, keeping her daughter out of the fight; she mentored Leia in statecraft and taught her the traditions of Alderaanian leadership. Breha remained on Alderaan to the end, dying in 0 BBY when the Empire destroyed the planet with the Death Star's superlaser.
Breha is born into Alderaanian nobility. Canon never gives a year; sources place her birth somewhere between 59 and 49 BBY.
Breha becomes Queen of Alderaan, heading the royal family and later serving as the planet's Minister of Education.
She weds Bail Prestor Organa, who represents Alderaan in the Galactic Senate while she rules from Aldera.
Complications during pregnancy nearly kill Breha and leave her with a cybernetic heart; the couple are unable to have a biological child.
At the end of the Clone Wars, Bail returns from Polis Massa with a newborn girl. Breha welcomes the infant, and the child is raised as Princess Leia Organa of Alderaan.
As the New Order tightens, Breha lends Alderaan's ships, credits and relief operations to the nascent rebellion her husband is helping to assemble, while keeping Leia's origins secret.
When Leia is kidnapped by agents seeking to blackmail Bail, Breha endures an agonizing wait on Alderaan until Obi-Wan Kenobi recovers her daughter and returns her home.
Breha presides over the ceremony in which the sixteen-year-old Leia claims her right to the throne, then works to keep her daughter clear of the rebel network she and Bail are building.
With the rebellion openly formed, Alderaan under Breha becomes one of its crucial covert backers.
Grand Moff Tarkin orders the Death Star to fire on Alderaan. Breha dies with her world and its billions of inhabitants.