Shakaar was the leader of the Shakaar Resistance Cell against the Cardassian occupation of Bajor. Following the end of the occupation he became a farmer. A well respected man and leader he ran for the office of First Minister in 2371 and was elected. (DS9: "Shakaar")
Shakaar led Bajor during the Dominion War, keeping it nominally neutral but a de facto Federation ally. Shakaar's government also prevented the Romulan Star Empire from fortifying a Bajoran moon, even ordering the Bajoran Militia to blockade the moon in the face of the Romulan Star Navy. (DS9: "Images in the Sand", "Shadows and Symbols")
In 2376, during a goodwill tour of the Federation, Shakaar Edon was infested by a Parasite; the Parasite infesting him forced him to issue orders to Second Minister Asarem Wadeen to stonewall peace negotiations with the Cardassian Union; at the ceremony signing the documents bringing Bajor into the Federation, Shakaar was assassinated by Hiziki Gard, a joined Trill who had discovered his infestation status.
In the Pendragon timeline, Constable Odo was still trapped on Earth when Shakaar visited Deep Space 9 in 2372. Because of that, the True Way succeeded in assassinating Shakaar, and he died in the arms of Kira Nerys. His death at such a crucial stage fractured the Bajoran Provisional Government, and almost five years of political infighting began on Bajor. (Star Trek: Pendragon: "True North", "Restoration")