The most important event was obviously the American Civil War from 1861-1865. This led to the 14th Amendment which defined a citizen as "any person born or naturalized in the US." The 13th Amendment abolished slavery, and the 15th Amendment prohibits denying the right to vote to someone because of their race.
Other key events include the Louisiana Purchase, the Texas Revolution, The Spanish-American War, the War of 1812, the purchase of Alaska, the Mexican Cession, the Indian Wars, and the California Gold Rush.
Like I said, the right to vote was extended to all male citizens by the 15th Amendment. Women were not given the right to vote until the 19th Amendment was passed in 1920.
Cuba gained independence from Spain, <span>Philippines was annexed and war torn, and Hawaii eventually became a US state. </span>
Principle 1All people are created equalPrinciple 2All people have basic rights that cannot be taken awayPrinciple 3The government gets its power to make decisions and to protect rights from the peoplePrinciple 4When the government does not protect the rights of the people, the people have the right to change or remove the government<span>
Hope this helps :)
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They got Taken over by Germany in WW1