Updated: Jan 31, 2019
HeritageQuest has a very useful and time-saving tool for visualizing changes to the United States since the time the first settlers arrived.
In 1790, for example, the following was different:
1) Maine was a part of Massachusetts.
2) Ohio, Indiana, Illinois, Wisconsin, Michigan, and parts of North Dakota, South Dakota and Minnesota, were called "Northwest Territory".
3) Tennesee was called "Southwest Territory".
4) Georgia included the northern parts of Mississippi and Alabama. The southern parts of Mississippi and Alabama were in dispute, having been claimed by both the U.S. and Spain.
5) Virginia included Kentucky and West Virginia.
6) North Carolina, South Carolina, Maryland, Delaware, New Jersey, Pennsylvania, New York, Connecticut, Rhode Island, New Hampshire, Maryland and Vermont were all established, although county and township divisions would still be made for many years.
7) The entire western portion of the United States was claimed by Spain, as was Florida and parts of modern-day Mississippi and Alabama. This included all the land now known as Louisiana, Arkansas, Missouri, Iowa, part of Minnesota, part of North Dakota, most of South Dakota, Nebraska, Kansas, Oklahoma, Texas, New Mexico, Colorado,Wyoming, Montana, Idaho, Utah, Arizona, Nevada, Washington, Oregon, and California.
By 1800, the following changes had been made:
1) The region formerly called "Northwest Territory", was now divided. The eastern part was still using the name "Northwest Territory" and included only Ohio and the eastern part of Michigan. The western part was now called "Indiana Territory" and included Illinois, Indiana, Wisconsin, the eastern part of Minnesota, and the western part of Michigan.
2) The southern portions of modern day Mississippi and Alabama were now called "Mississippi Territory".
3) Kentucky was formed from the western portion of Virginia, which still included both Virginia and West Virginia.
By 1810, the following changes had been made:
1) Michigan Territory, Ohio, and Indiana Territory were established. No longer was the region called the "Northwest Territory". The part of Michigan that is across Lake Michigan was part of Indiana Territory.
2) Illinois, Wisconsin, and eastern Minnesota were called "Illinois Territory".
3) Modern-day Louisiana was called "Orleans Territory".
4) The mid-western portion of the United States was called "Louisiana Territory" and encompassed modern-day Arkansas, Oklahoma, northern Texas, northeasern New Mexico, eastern Colorado, Kansas, Missouri, Iowa, Nebraska, southwestern Minnesota, southwestern North Dakota, eastern Wyoming, and almost all of Montana and South Dakota.
5) Georgia was reduced to it's present size. All of modern-day Missippi and Alabama were called "Mississippi Territory".
6) The Spanish still held the west, including Washington, Idaho, western Montana, California, Nevada, Utah, southwestern Wyoming, Utah, western Colorado, Arizona, western New Mexico, and central and southern Texas.
By 1820, the following changes had been made:
1) Modern-day Maine was established, with the northern part being claimed by both the U.S. and Britain.
2) Alabama was fromed from Mississippi.
3) Orleans Territory's name was changed to Louisiana.
4) Modern-day Arkansas and Oklahoma were now called Arkansas Territory.
5) Michigan Territory was expanded to include Wisconsin and the region north of Lake Michigan (formerly called Indiana Territory), as well as eastern Minnesota.
6) Illinois Territory was divided to contain only modern-day Illinois.
7) Arkansas Territory was formed and included modern-day Oklahoma and Arkansas.
8) Missouri Territory was formed and included modern-day Missouri, Iowa, western Minnesota, North Dakota, South Dakota, Nebraska, most of Kansas, northeastern Colorado, northeastern Wyoming, and eastern Montana.
9) Washington, Oregon, Idaho, northwestern Montana, and western Wyoming were jointly occupied by the U.S. and the British.
10) The Spanish still held the western part of Colorado, southwestern Kansas, northwestern Oklahoma, Texas, New Mexico, Arizona, Utah, southwestern Wyoming, Nevada and California. The land was referred to as "Spanish Mexico".
By 1830, the following changes were made:
1) Florida was established, and was no longer under Spanish occupation.
2) Arkansas Territory was divided to include only modern-day Arkansas.
3) Missouri Territory was reduced to include only modern-day Missouri, with the exception of the northwest corner of the state.
4) Michigan Territory still encompassed all of Michigan and Wisconsin, and part of Minnesota.
5) The west was still referred to as Spanish Mexico, encompassing all of California, Nevada, Arizona, Utah, New Mexico, and Texas, as well southwestern Wyoming, western Colorado, and northwestern Oklahoma.
By 1840, the following changes were made:
1) Wisconsin Territory was broken off from Michigan Territory and included the eastern part of modern-day Minnesota.
2) Michigan Territory reached its modern-day borders and was called Michigan.
3) Iowa Territory was established and encompassed modern-day Iowa, western Minnesota, eastern North Dakota, and eastern South Dakota.
4) The Republic of Texas was formed, encompassing the central and eastern portioni of modern-day Texas. The remainder of Texas had been claimed by Texas, but the land was still controlled by Mexico.
By 1850, the following changes were made:
1) The land north of Maine, which had formerly been claimed by both Britain and the U.S., was annexed to Maine.
2) Wisconsin was slightly reduced, reaching its modern-day boundaries.
3) Iowa Territory was divided and reached its modern-day boundaries.
4) Minnesota Territory was divided from Iowa Territory and included modern-day Minnesota and the eastern Dakotas.
5) California, Texas and Oklahoma reached their modern-day borders.
6) New Mexico Territory was formed, encompassing modern-day New Mexico, southern Colorado, Arizona, and southern Nevada.
7) Utah Territory was formed, encompassing Utah, western Colorado, central and northern Nevada, and southwestern Wyoming.
8) Oregon Territory was formed, encompassing modern-day Oregon, Idaho, Washington, western Montana, and western Wyoming.
By 1860, the following changes were made:
1) Minnesota was divided, reaching its modern-day borders. The land to the west was called the Dakota's, "Indian Territory".
2) Modern-day Oklahoma's boundaries were established and it was also Indian Territory.
3) Kansas Territory was formed, encompassing Kansas and central and eastern Colorado.
4) Nebraska Territory was formed, encompassing modern-day Nebraska, northwestern Colorado, central and eastern Wyoming, central and eastern Montana, western North Dakota, and western South Dakota.
5) Oregon Territory was reduced, establishing its modern-day borders.
6) Washington Territory was formed from Oregon Territory and it encompassed modern-day Washington, Idaho, and northwestern Montana.
By 1870, the following changes were made:
1) West Virginia was divided from Virginia.
2) Idaho was divided from Washington, reaching its modern-day boundaries.
3) Nevada and Colorado were formed from Utah Territory, reaching their present-day boundaries.
4) Arizona was formed from New Mexico, both states establishing their present-day boundaries.
5) Kansas reached its present-day boundaries, its western portion established as the state of Colorado.
6) Montana reached its present-day boundaries.
7) Modern-day North Dakota and South Dakota were unified and called "Dakota Territory".
8) Alaska was now a U.S. possession, being purchased from Russia in 1867. It became a Territory in 1912, and a state in 1959.
In 1880, modern-day North Dakota, South Dakota, and Oklahoma, were still Dakota Territory and Indian Territory. By 1890, these states established their modern-day borders, with portions of Oklahoma being Indian juristictions from 1890 to 1907. Hawaii was annexed to the U.S. in 1898, became a territory in 1900, and finally, a state in 1959.
The divisions of each of the states, into counties, towns, cities and villages, is another story. If you can access HeritageQuest, they provide maps illustrating the changes for each state (click here).
See also "Map Guide to the U.S. Federal Censuses, 1790-1920", by William Thorndale and William Dollarhide, 1987. Click here to buy it on Amazon.