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In page Nicaragua:

"

Invited by the Liberals in 1855 to join their struggle against the Conservatives, the American adventurer and filibuster William Walker set himself up as President of Nicaragua after conducting a farcical election in 1856; his presidency lasted less than a year.[5] Military forces from Costa Rica, Honduras, El Salvador, Guatemala, and Nicaragua itself united to drive Walker out of Nicaragua in 1857,[6][7][8] bringing three decades of Conservative rule.[citation needed]