The United States currently has 50 states within the union, but there could be more coming in the future. Puerto Rico is pushing to become the 51st state, according to Vox. Right now citizens on the island aren't allowed to vote in presidential elections. Washington, D.C., is another contender to become the 51st state. According to the New Yorker, there was a vote as recently as this year to give the district statehood (though it later failed).
It's been a long 60 years since a new state entered the union. This is how the ten most recent states became a part of the nation:
Montana
According to Montana's official state website, the state joined the union on November 8, 1889. Before it became a state, it was an official territory of the U.S., settled by many different tribes of Native Americans. It was part of the Lewis and Clark expedition, and the famed explorers mapped out the area as well as noted the resource-rich lands. Mining brought industry, starting the movement to become a state. The Homestead Act brought a flood of settlers to the area just 20 years after it achieved official statehood.
Washington
Washington attained statehood status on November 11, 1889, according to the Seattle Times. That's just three days after Montana, and that's not a coincidence. The two territories were able to gain statehood thanks to a law passed by Congress. The law allowed several territories to adopt statehood status. Washington was one of four states to join the union in November of 1889. The others were Montana, South Dakota, and North Dakota.
Idaho
Idaho joined the union on July 3, 1890, making it the 43rd state. Idaho was another state with territory status before joining the union, lumped in with the areas that we now call Oregon and Washington. The state's population boomed thanks to a gold rush in the 1860s. But it was the Mormon settlers who helped establish statehood. They wanted more influence in Congress and pushed for Idaho to be formally recognized as a state.
Wyoming
The former U.S. territory became a state on March 27, 1890. But statehood wasn't attained easily. When the territory was formed in 1869, talk about statehood began but petitions were later rejected by Congress. Wyoming residents decided to carry on as if they'd gained statehood, writing a state Constitution later that year. So lawmakers in Washington, D.C., decided to go ahead and make it official. Interestingly, Wyoming was the first state in the union to allow women to vote, according to WyoHistory. They passed the law in 1869, a full 11 years before the territory became a state.
Utah
The fight for statehood was a long one for Utah, drawn out over 50 years and numerous petitions to Congress, according to the state website. The hang-up was polygamy. Utah had a large Mormon population, and polygamy was then a tenet of the religion. But since it was one highly frowned upon by Christian leaders in Washington, Congress finally agreed to make Utah a state only if local lawmakers would write a ban on polygamy into the state constitution. They did, and Utah became the 45th state of the union on January 4, 1896.
Oklahoma
While states were joining the union rapidly before the turn of the century, there would be an 11-year gap between the 45th and 46th state. Oklahoma didn't attain statehood until November 16, 1907. According to the Oklahoma Historical Society, the push for statehood came from settlers moving into the territory during the land rush in 1889. They wanted equal representation in Congress. But quarrels with Native Americans delayed statehood. Native American tribes in the area wanted to form their own state called Sequoyah. Unable to gain political traction for the movement, Congress later joined the Indian Territory of Sequoyah with Oklahoma to form a single unified state.
New Mexico
New Mexico is an area that passed hands several times before attaining statehood. It was originally owned by Spain but gained its independence in 1812. It then became a province of Mexico. The Mexican–American war of 1846 saw much of the area captured by American soldiers. The rest of the territory came thanks to the Treaty of Guadalupe Hidalgo in 1848. The population grew significantly in the area due to the introduction of the railway. Settlers in the New Mexico territory petitioned Congress for statehood, and New Mexico became a state on January 6, 1912.
Arizona
Arizona became a state on February 14, 1912. That was after nearly 50 years of fighting for the privilege, according to The Arizona Republic. Residents within the New Mexico territory petitioned to form their own state of Arizona but were continually denied. That was part of the reason the area decided to join the Confederate States in the Civil War, becoming the Confederate Territory of Arizona. It would be another 50 years before Arizona would become a state of the union. At first, Congress proposed bringing it into the Union as part of New Mexico, but Arizonians didn't want to lose their identity. So they protested and petitioned repeatedly, drafting a state constitution that was later rejected. After some rewrites, Arizona lawmakers finally came to an agreement with the U.S. government and became the 48th state.
Alaska
It would be another 47 years before another state entered the union. That state was Alaska, which gained statehood on January 3, 1959. The United States had owned the territory of Alaska since 1867 when President Andrew Johnson bought it from Russia for $7.2 million. That purchase was largely viewed as a mistake until miners discovered gold in 1897. The gold rush brought thousands of Americans to the territory, establishing booming mining and fishing industries. Alaskans voted in favor of statehood in the midst of World War II, when military bases in the territory kept Japanese invasions at bay. It took Congress until long after the war ended to make statehood official.
Hawaii
Hawaii was the most recent state to join the union, gaining statehood on August 21, 1959. That was just eight months after Alaska, and the two came into the union due in large part to the events that happened in World War II. Hawaii had been a territory of the United States since 1898, coming under the protection of the U.S. due to the influence of American plantation owners. They wanted the protection and resources of the United States, but they also wanted to be exempt from import taxes. Hawaiians would later petition for statehood many times but without any luck. American citizens viewed the land as too far away to be a state.
But with the outbreak of World War II, Hawaii's location became a big deal — and a big advantage to the military. The bombing of Pearl Harbor in 1941 launched the U.S. into the war, and the Hawaiian Islands were a strategic base for the fight against Japan. After the war, citizens of Hawaii again petitioned for statehood, pointing out that they'd been unswervingly loyal to the United States. Finally, more than 60 years after coming under the rule of the U.S., Hawaii gained statehood status and became the 50th state of the union.