The Neimoidian Civil War was fought between factions on the Neimoidian purse worlds during the Imperial era after the subjugation of the Trade Federation, which served as the corporatocratic government of these worlds before becoming a puppet of the Galactic Empire (overseen by Baron Merillion Tarko). Some Neimoidians sought to form a monarchy (led by an unrecognized "Royal House of the Neimoidian Worlds"), others wished to reestablish a Separatist corporatocracy similar to the Trade Federation, and most simply accepted the Imperial regime.
The Neimoidian Gunnery Battalions, who served as the purse worlds' security forces, continued operating as a resistance movement against the Imperials in support of the corporatocrats and later allied themselves with the Rebel Alliance. Many Neimoidian warlords and governors also kept using Separatist warships and battle droids in their campaigns.