It is unknown when Ramedar became King, but he was the ruler of the nation during part of the Consolidation, Artur Hawkwing's war of conquest which saw him take control of all the Westlands over a twenty-year period. For much of that time, Aldeshar was part of a coalition of nations waging war against Hawkwing, according to some histories at the direction of Bonwhin Meraighdin, the Amyrlin Seat of the Aes Sedai at the time.
Aldeshar was the final kingdom to succumb to Hawkwing's forces. Hawkwing conquered the nation in FY 963. However, Hawkwing held Ramedar to blame for the death of his wife Amaline Paendrag Tagora from poison, along with three of his children, three years earlier. Hawkwing was unusually cruel and ruthless in his treatment of Aldeshar, scattering its nobility across the continent. Ramedar's fate is not recorded, but given Hawkwing's fury at the time, it is presumed that he was executed.
Hawkwing later regretted his treatment of Aldeshar and restored Ramedar's daughter Endara Casalain to titles and honors, making her the governor of the Imperial Province of Andor. Endara's daughter Ishara founded the kingdom of Andor during the opening year of the War of the Hundred Years and established an unbroken bloodline that remains strong today, a thousand years on. Joal Ramedar is hence the direct ancestor of most of the great houses of Andor.