How the United States expanded by buying territories. Major US acquisitions of the last 200 years
The United States has expanded its territory throughout history, through acquisitions and cessions that have shaped its current map, and which it now aspires to expand again with the acquisition of Greenland, writes the EFE agency on Wednesday, quoted by Agerpres.
US President Donald Trump would be willing to buy Greenland, as Secretary of State Marco Rubio confirmed to a group of lawmakers. Rubio added that his advisers are preparing an updated plan to find a way to acquire this autonomous territory from the Kingdom of Denmark.
Over the past 200 years, these are the main transactions made by US administrations:
Louisiana Purchase (1803)
In 1803, the United States purchased the vast territory of Louisiana from France for $15 million. This agreement, promoted by President Thomas Jefferson and accepted by Napoleon Bonaparte, marked the beginning of a policy of growth that defined the modern map of the United States.
The agreement allowed the country to double its area and consolidate its westward expansion. The US incorporated nearly 1.3 million square kilometers, accounting for 23.3% of its current land area.
Florida (1819)
Spain ceded eastern Florida to the United States through the Adams-Onis Treaty, signed in 1819 and ratified in 1821. It was not an outright purchase with cash payment, but rather a cession by Spain in exchange for five million dollars intended to settle the claims of American citizens against Spain.
The Sabina and Arkansas Rivers were chosen as the boundary between the Spanish and American possessions, a boundary line completed by the area bounded by the 42nd parallel.
Texas and the Mexican Cession (1845-1848)
Texas, which had declared independence from Mexico in 1836, joined the United States in 1845.
Three years after the Mexican-American War, the Treaty of Guadalupe Hidalgo established the so-called Mexican Cession: Mexico ceded vast territories—present-day California, Nevada, Utah, Arizona, and parts of Colorado and New Mexico—in exchange for $15 million and the payment of a $3.2 million debt.
Purchase of the Alaska Territory (1867)
The purchase of Alaska was completed on October 18, 1867, when Russia sold this territory to the United States for $7.2 million, equivalent to about $4.73 per square kilometer.
The agreement was promoted by Tsar Alexander II, who sought to prevent the British Empire from conquering the region after the Crimean War.
The transaction, considered the first ceding of territory by Russia, was later seen as a strategic error, as Alaska proved to be an area rich in natural resources and of great geopolitical value. At the time, the deal was criticized by the press and by figures such as Karl Marx.
Virgin Islands (1917)
In 1917, Denmark sold the Danish West Indies, now known as the US Virgin Islands, to the United States for $25 million in gold. The transaction included the islands of St. Thomas, St. John and St. Croix, as well as other smaller islands.
The transaction was part of US efforts to expand its influence in the Caribbean beginning in 1867.
Other acquired territories
In 1898, after the war with Spain, the United States obtained Puerto Rico and Guam through the Treaty of Paris and annexed Hawaii the same year. Although not all of these acquisitions were outright acquisitions, they were part of the country's territorial expansion.
And now Greenland
As early as the mid-19th century, the United States expressed interest in acquiring Greenland. As early as 1946, then-President Harry Truman offered Denmark $100 million for the island.
With the arrival in power of Donald Trump, during his first term (2017-2021), interest in acquiring the autonomous territory of Denmark has been rekindled.
Danish Prime Minister Mette Frederiksen stressed that “Greenland is not for sale,” a refusal that prompted Trump to cancel an official visit planned for September 2019, sparking a brief diplomatic crisis.
During his second term, the Republican revived his Greenland ambition. In December 2024, he declared that “ownership and control” of the island was an “absolute necessity” for US national security.
On Wednesday, Secretary of State Marco Rubio confirmed that Trump “would be willing to buy Greenland” and that his advisers are preparing an updated plan to purchase the territory.
