Walker - The amazing story of a real life American soldier of fortune (Ed Harris)

Walker is a 1987 historical Weird Western film directed by Alex Cox and written by Rudy Wurlitzer. It stars Ed Harris as William Walker, the American filibuster who invaded and made himself president of Nicaragua. The cast also features Richard Masur, René Auberjonois, Peter Boyle, Miguel Sandoval and Marlee Matlin.

In 1853, soldier-of-fortune William Walker flees Mexico, after a failed attempt to incite an armed insurrection. He is placed on trial by US official for breaking the Neutrality Act, but wins an acquittal after giving a rousing speech to the jury. Walker has plans to settle down and start a newspaper, however, his fiancée Ellen Martin dies of cholera. Afterwards, American multimillionaire Cornelius Vanderbilt offers a job to Walker to bring stability to Nicaragua by assisting the Democratic Party in its civil war against the Legitimists. Doing so would secure Vanderbilt's rights over an overland shipping route between the Atlantic Ocean and the Pacific Ocean. Walker, who is a firm believer in Manifest Destiny, accepts and hires 60 mercenaries to join him on his mission.

Despite significant losses, Walker and his company score a bloody victory in Nicaragua, first in Rivas and then in the Conservative capital of Granada. In the midst of battle, Walker calmly strolls through the battlefield, seemingly unconcerned by the gunfire and death surrounding him. When the capital falls, Walker allows the President to stay in charge while the president's mistress, Doña Yrena, seduces Walker. After discovering that the President is attempting to rally other countries in Central America to unite and repel the Americans, Walker orders the President executed for treason and assumes the presidency for himself via a rigged election. From 1855 to 1857, his actions as president become increasingly manic and delusional, with Walker antagonizing his financial backer by revoking Vanderbilt's license to the overland trade route and seizing his ships. When one of Walker's brothers challenges his authority, Walker kills him without hesitation. Cut off from supplies and reinforcements, he decides to introduce slavery to Nicaragua in an attempt to gain support among the Southern U.S. states, causing the African-American members of his legion to quit in protest. The situation continues to deteriorate as neighboring countries invade Nicaragua. Yrena returns and attempts to convince Walker to stop the carnage - when he refuses, she attempts to kill him, but fails and is forced to run away. Incensed, Walker instructs his men to burn down the town. Taking refuge in the church, Walker gives one final speech to his few remaining men and the Nicaraguan prisoners, stating that the day will never come where America will leave Nicaragua alone, as "it is America's destiny" to be there.