Sermeria was an agricultural world situated within the Expansion Region; it was considered an agriworld.
As early as 1019 BBY, Sermeria was a tranquil agriworld under the Galactic Republic, the same year that Johun Othone, the future Jedi Knight, was born in Addolis, its capital.
During the Republic's decline, Lanus Wrede served as its representative in the Galactic Senate. After Baktoid Armor Workshop and the Techno Union ceased production of B1-series battle droids at factories on five separate planets, Wrede alleged that the Techno Union had moved their operations to the Outer Rim Territories. Wrede pointed out that the Techno Union kept purchasing raw materials, but had not manufactured any products during the same period. He had no evidence to back up his claims, and several business analysts disputed his statement. After a three-month investigation found no evidence, Wrede's political career and reputation were ruined. Wrede then committed suicide. In truth, Wrede's suspicions were accurate, and these hidden battle droids would soon emerge from planets like Geonosis during the Clone Wars.
Senator Ister Paddie took Wrede's place in the Senate. When Corellia closed its borders in defiance of the Military Creation Act, Paddie denounced their actions as self-serving. He emphasized that his sector had fewer resources than the Corellians, possessing less than a third of their wealth, but had remained loyal to the Republic.
Shortly thereafter, a suspicious package was delivered to the Sermerian First House in Sermeria's capital city. A cleaning droid discovered the package concealed behind a planter in the building's lobby, and upon opening it, it was found to contain an effigy of Supreme Chancellor Palpatine covered in stone mites. The package was addressed to both Senator Paddie and President Dibra Born. Although the government was temporarily shut down, bomb-squad droids and the Sermerian Bio-League were able to contain the threat.
When Palpatine established the Loyalist Committee, Senator Paddie was appointed as a member of the ten-member group, representing the interests of the Expansion Region.