The United States has more or less run out of new areas to add as states—although President Donald Trump has expressed an interest in changing this.

When the Declaration of Independence was signed just over 250 years ago, the population of the United States stood at roughly 2.5 million. Today, it has grown to a whopping 342 million—making America the third-most populous country on Earth, behind India and China (1.4 billion each) and ahead of Indonesia (287 million).

Of course, there are two things to consider. First, the United States has nine times the land area in 2026 as it did in 1776, growing from just 430,000 square miles then to approximately 3.8 million square miles today.

Second, just 50 years ago, as the United States was celebrating its bicentennial, there were roughly 218 million Americans. Today, that number has swelled by 58 percent, and Americans account for 4.2 percent of the global population. The population increase of the last half-century was largely driven by significant net immigration and longer life spans. Current demographic trends suggest that the United States will level off at a population of around 370 million in the 2080s, before beginning a slow decline.

One curious note is that in the last 50 years, the United States may have seen a massive population growth, but it saw the addition of no new states for all of the new people. That point might not seem all that noteworthy, but in every other 50-year span of the 250 years since the signing of the Declaration of Independence, at least a couple of states joined the union. In all of the nation’s quarter of a millennium of existence, the last 67 years have seen no new states admitted—though sometimes not for lack of trying.

How America Got from 13 States to 48

Between 1776 and 1826, a total of 11 states joined the United States. The original 13 colonies were, in chronological order of their ratification of the US Constitution: Delaware, Pennsylvania, New Jersey, Georgia, Connecticut, Massachusetts, Maryland, South Carolina, New Hampshire, Virginia, New York, North Carolina, and Rhode Island.

When the United States won independence from Great Britain, it was also ceded British territory to the west of the established colonies. Rather than planning to split that territory among existing states, Congress established a framework for creating new states in the Northwest Ordinance of 1787.

The first case was the addition of Vermont, which entered the Union in March 1791. Vermont’s case was unusual, as settlers there had formed their own government and constitution in 1777—meaning that the territory operated as an independent nation, the Vermont Republic, for 14 years. The Continental Congress initially refused to recognize Vermont’s statehood to avoid angering New York, which also claimed its territory. To head off New York’s encroachment, Vermont even briefly considered rejoining the British Empire through Canada. Fortunately for the young United States, cooler heads prevailed.

The next states to join the union were Kentucky, Tennessee, Ohio, Louisiana, Indiana, Mississippi, Illinois, Alabama, Maine, and Missouri, which each applied for statehood as their populations reached the level established under the Northwest Ordinance. Much of this expansion was fueled by the Louisiana Purchase, doubling the size of the United States and opening the American interior to further settlement. Maine joined the Union in 1820; it seceded from the state of Massachusetts, which had previously controlled its territory.

Between 1826 and 1861, the greatest number of states joined the union in a single 50-year period, including Arkansas, Michigan, Florida, Texas, Iowa, Wisconsin, California, Minnesota, Oregon, and Kansas—with political disputes and violence over the latter’s status as a free or slave state a major contributor to the Civil War. Texas was famously a fully recognized independent, sovereign nation from 1836 to 1845; its eventual annexation by the United States was a cause of the Mexican-American War, which added further territory for future states. California also declared independence from Mexico for about a month in 1846 before it entered the United States, but received no foreign recognition.

West Virginia was the final state to join the Union that was carved out entirely from an existing state without the addition of any new federal territory. It was formed from the 39 counties in western Virginia that voted against Virginia’s secession in 1861; when the rest of the state joined the new Confederacy, they remained in the Union, receiving statehood in 1863. Nevada joined the following year, rushed into statehood by Republicans in Congress to give President Abraham Lincoln a better chance in the 1864 presidential election.

Nebraska became the first state to enter the Union after the Civil War, admitted in 1867. It joined after Congress overrode a veto by President Andrew Johnson, who was unhappy that Black Nebraskans were allowed to vote.

So it was that on July 4, 1876, in the first centennial since the Declaration of Independence, there were 37 states. Less than a month later, on August 1, Colorado became the 38th state—giving it its moniker as the Centennial State.

By the 150th anniversary on July 4, 1926, 10 other states joined the union: North Dakota, South Dakota, Montana, Washington, Idaho, Wyoming, Utah, Oklahoma, New Mexico, and Arizona. The latter two joined in January and February 1912, respectively, completing the statehood map for the lower 48 states and making the stars on the American flag very easy to draw.

How Did Alaska and Hawaii Get Statehood?

Those two final states are also a bit unique in their respective path to statehood. 

Alaska didn’t exactly fit the traditional concept of Manifest Destiny, as some Founding Fathers may have seen it. Yet William H. Seward, a devout believer in expansionism who served as Secretary of State from 1861 to 1867, championed the $7.2 million (~$150 million in 2026 dollars) purchase of the territory from Russia. At the time, the purchase was derided as “Seward’s folly,” as Alaska was a desolate wilderness with few people. Yet the purchase solidified American dominance across the Pacific and limited British influence, and eventually opened Alaska’s vast natural resources to American exploration. The purchase also increased the nation’s physical size by about 23 percent—equaling the area of Texas, California, and Montana combined!

Apart from the Republic of Texas, the Kingdom of Hawaii (1795 to 1893) was the only other independent country to later become a state. The part of the history that isn’t so convenient for America is that wealthy American sugar planters, backed by the US military, overthrew the native Hawaiian monarchy and arranged for the island’s annexation for financial reasons. It remained a US territory until residents voted overwhelmingly—94 percent—in a 1959 referendum to become the 50th state. Washington has since acknowledged its responsibility for the kingdom’s downfall, which included the 1993 Apology Resolution that was signed by President Bill Clinton.

It should be noted that Hawaii was never given the option of independence during the statehood vote, with residents only voting whether it should remain a territory or become a state. This has led to a modern movement for Hawaii’s independence, although polling suggests that most Hawaiians today are content with Hawaiian statehood in spite of its troubled origins.

Some Other Places Narrowly Missed US Statehood

There were several “proposed” states over the past 250 years as well. Those included the proposed State of Sequoyah, which was drawn up by the “Five Civilized Tribes,” the Cherokee, the Choctaw, the Creek, the Chickasaw, and the Seminole. Congress rejected that idea; instead, the Indian Territory was merged with what became Oklahoma.

There was also the proposed State of Deseret, which would have included all of modern-day Utah and Nevada, along with territory in several modern adjacent states. Mormon pioneers in the territory, led by Brigham Young, floated the idea before Congress in the late 1840s. Congress rejected it, in part because of outrage over the Mormon practice of polygamy. After the Mormons abandoned polygamy in 1890 following pressure from the US government, the much smaller state of Utah entered the Union in 1896.

Among the forgotten “almost states” is the now-independent nation of the Philippines. It was never on a realistic path to becoming a state, but there was a push by a faction of Filipino elites who sought the same economic advantages the American planters in Hawaii had. It failed to gain traction due to widespread opposition—both from Filipinos who wanted total independence and from American lawmakers who opposed the distance and saw Filipinos as unfit for US citizenship due to the pervasive racial and religious prejudices of the era.

Could There Be Future States? Trump Has a Few in Mind

Could we see another state in the next 50 years? President Donald Trump would certainly like to think so. He has repeatedly called for Canada to become the 51st state—an idea that hasn’t gone over well with the Canadians themselves. Trump and his allies have likewise called for the US to annex Greenland, an autonomous territory within the Kingdom of Denmark.

Neither place is a likely option for a future state. Setting aside the issue of the near-total opposition to US annexation within Canada itself, America’s northern neighbor is even larger than the United States by land area and would be far too big to be admitted as a single state. Admitting individual provinces as states poses its own problems. Prince Edward Island, the smallest Canadian province, has a population of only around 150,000—around one-fourth that of Wyoming, the smallest existing US state by population—and Canada’s northern territories are smaller still. There is also the issue of Quebec, which has long had a complicated relationship with the rest of Canada. A US annexation of Canada under any terms would probably trigger the Quebecois to seek independence once more.

Greenland faces similar issues, with the majority of its population of roughly 60,000 favoring full independence rather than absorption into the United States.

That leaves just two realistic options for future states: Puerto Rico, a US territory in the Caribbean, and Washington, DC, the capital, which lacks representation in Congress. Even as residents in both have shown an interest in statehood, it would ultimately be up to Congress to approve. Given that both jurisdictions lean heavily towards the political left, it is unlikely that Trump or a veto-armed Republican bloc would ever support either for statehood.

All that largely explains why, for the past 67 years, we have not seen another state join the union—and why we will likely reach the tricentennial with only 50 states!

About the Author: Peter Suciu

Peter Suciu has contributed to dozens of newspapers, magazines and websites over a 30-year career in journalism. He regularly writes about military hardware, firearms history, cybersecurity, politics, and international affairs. Peter is also a contributing writer for Forbes and Clearance Jobs. He is based in Michigan. You can follow him on Twitter: @PeterSuciu. You can email the author: Editor@nationalinterest.org.

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