From 13 colonies to 50 states
The 13 colonies achieved independence from Britain until 4 July 1776.
Since then, they continued adding more land to their territory until they reached the 50 states they now possess.
The Republic of Vermont was a de facto independent country, it was admitted as the 14th state.
It became Vermont.
Virginia’s western counties beyond the Appalachian Mountains are separated and admitted as the 15th state.
The Southwest Territory was admitted as the 16th state.
The southeastern part of the Northwest Territory was admitted as the 17th state.
Orleans Territory was admitted as the 18th state.
The southern part of the Indiana Territory was admitted as the 19th state.
The Territory of Mississippi was admitted as the 20th state.
The southern part of the Illinois Territory was admitted as the 21st state.
The Alabama Territory was admitted as the 22nd state.
The Maine District of Massachusetts split up and was admitted as the 23rd state as part of Missouri’s engagement.
The southeast corner of the Missouri Territory was admitted as the 24th state.
The Territory of Arkansas was admitted as the 25th state.
The Territory of Michigan was admitted as the 26th state.
Florida Territory was admitted as the 27th state.
The Republic of Texas was admitted as the 28th state.
The southeastern part of the Territory of Iowa was admitted as the 29th state.
The southeast of the Wisconsin Territory was admitted as the 30th state.
The Mexican Cession was divided as part of the 1850 Commitment. The western part was admitted as the 31st state.
The eastern part of the Minnesota Territory was admitted as the 32nd state.
The western part of the Oregon Territory was admitted as the 33rd state.
The eastern part of the Kansas Territory was admitted as the 34th state.
Several counties in northwestern Virginia, who did not want to be part of the Confederation, separate and are admitted as the 35th state.
The Nevada Territory was admitted as the 36th state.
The Nebraska Territory is admitted as the 37th state.
The Territory of Colorado is admitted as 38th state.
North Dakota is admitted as the 40th state.
South Dakota is established as the 40th state.
Montana Territory was admitted as the 41st state.
Washington Territory was admitted as the 42nd state
The Idaho Territory was admitted as the 43rd state.
The Wyoming Territory was admitted as the 44th state.
Utah Territory was admitted as the 45th state.
The Oklahoma Territory and the Indian Territory are combined and admitted as the 46th state.
The Territory of New Mexico was admitted as the 47th state.
The Arizona Territory is admitted as the 48th state.
The Territory of Alaska was admitted as the 49th state.
The Territory of Hawaii was admitted as the 50th state.
It became Kentucky.
It became Tennessee.
It became Ohio.
It became Luisiana.
It became Indiana.
It became Mississippi.
It became Illinois.
It became Alabama.
It became Maine.
It became Missouri.
It became Arkansas.
It became Michigan.
It became Florida.
It became Texas.
It became Iowa.
It became Wisconsin.
It became California.
It became Minnesota.
It became Oregon.
It became Kansas.
It became West Virginia.
It became Nevada.
It became Nebraska.
It became Colorado.
It became North Dakota.
It became South Dakota.
It became Montana.
It became Washington.
It became Idaho.
It became Wyoming.
It became Utah.
It became Oklahoma.
It became New Mexico.
It became Arizona.
It became Alaska.
It became Hawaii.
The rest became unorganized territory.
The rest of the Northwest Territory was transferred to the Territory of Indiana.
The rest became unorganized. Missouri did not include the current northwest triangle, which was added later by the purchase of the Platte.
The Miller County claim continued, with growing irrelevance.
It was annexed by the United States on March 1, 1845, but Texas did not agree to join the Union until some time later.
Brought with it all the lands of Mexico he claimed, including all of present-day Texas and parts of Colorado, New Mexico, Oklahoma and Wyoming. With joining the Texas Union, Arkansas finally waived its claim over Miller County.
The rest became unorganized territory.
The rest was organized as Utah Territory and New Mexico Territory.
Both territories also include lands ceded to the federal government by Texas in exchange for assuming its debts; a part of Texas and the Cession of Mexico became unorganized territories.
The rest was assigned to Washington Territory.
It was a bit smaller than it is today, lacking some areas both in the east and south.
The Dakota Territory was divided into two.
The acquisition of Hawaii ultimately results in the current configuration of the United States. 
The Louisiana Purchase, the expansion of the United States west of the Mississippi River, took place. The purchase extended slightly north of the modern borders, as it was defined only as the Mississippi River Basin.
The Louisiana Purchase was divided into the Louisiana District, which was temporarily under the authority of the Indiana Territory and the organized Orleans Territory, which corresponded to part of the current state of Louisiana with a small part of Texas.
The Louisiana District was organized as the Louisiana Territory.
The Republic of Texas achieved independence from Mexico, although with a large part of the disputed territory.
It has the control of the eastern half of present-day Texas, and in dispute was the western half, as well as parts of Colorado, Kansas, New Mexico and Wyoming.
The Treaty of Guadalupe Hidalgo, which ended the Mexican-American War, and, Mexico ceded a vast area of land to the United States, known as the Mexican Cession, which consisted of all of today’s California, Nevada and Utah, most of Arizona, and parts of Colorado, New Mexico and Wyoming.
The Gadsden Purchase added some land to the Territory of New Mexico, corresponding to the southern parts of the current states of Arizona and New Mexico.
The United States buys Alaska from Russia, being designated as the Department of Alaska, corresponding, with the exception of a small border dispute, to the current state of Alaska.
The Department of Alaska, previously under the direct control of the federal government and the army, was renamed the Alaska District, forming its own local government.
The District of Alaska was organized as Alaska Territory.
The 1818 Treaty established the 49th North parallel west of Lake Forest as the border with British lands and established Oregon Territory as a shared land between the United States and the United Kingdom.
The treaty transferred the Red River Basin to the United States, which consisted of northwest Minnesota, northeast North Dakota and northeast South Dakota.
In 1821 the Adams-Oni Treaty entered into force, establishing the entire US border. and the New Spain, being all the Spanish Florida sold to the USA.
The treaty transferred the remainder of today’s Idaho and Oregon to the Territory of Oregon; it moved parts of today’s Colorado, Oklahoma and Wyoming and all of New Mexico and Texas to New Spain, and all of Florida to the United States.
The Oregon Territory was organized, including today’s Idaho, northwestern Montana, Oregon, Washington and western Wyoming.
The Hawaiian Islands were unified as the Kingdom of Hawaii.
The Kingdom of Hawaii becomes the Republic of Hawaii.
The Republic of Hawaii was annexed to the United States.
The annexed Hawaiian islands are organized in the Territory of Hawaii.
The purchase consisted of all the current states of Arkansas, Kansas, Iowa, Missouri, Nebraska and Oklahoma and parts of Colorado, Louisiana, Minnesota, Montana, New Mexico, North Dakota, South Dakota, Texas and Wyoming.