<Li> William Bonney a.k.a. Henry McCarty a.k.a. Billy the Kid, Wild West, outlaw </Li> <Li> John Wilkes Booth, the assassin of president Abraham Lincoln </Li> <Li> James Bowie, Soldier, Texan who died at the Alamo, invented the Bowie knife </Li> <Li> Jim Bridger, Wild West, mountain man </Li>

Which one of the following can be called as a major event of the 19th century