Historical boundaries - (one of the reasons Why we can't find our ancestors on some USA census records). The first US census was in 1790. Previous to that look elsewhere.
Pay close attention to which state was what by the year they became a state. Even though your ancestor was born and raised in what is now the United States, they may have been in another country. Hopefully these maps and dates will help. In 1700 the other countries were American Indian Tribes, Britain, Spain & France. the Revolution took from about 1775-1778

The first Colony was Virginia and it was from North of the Hudson in New York through South Carolina. When England got a taste of Tobacco (the main crop), the King appointed governors and the governors gave away land free to the settlers who would farm the land of VA. Each Governor was given a section of land in VA to control. The 13 Colonies were born from these appointments.
If you are looking for ancestors who settled in the early 1600s, the settled in the VA that covered a large area. The records will probably be in Great Brittan.
13 Original Colonies: Massachusetts, New Hampshire, Connecticut, Rhode Island, New York, Pennsylvania, New Jersey, Delaware, Maryland, Virginia, North Carolina, South Carolina and Georgia. The records will probably be in Great Brittan.
These colonies were appointed Governors to oversee them and each Governor was able to make his own rules and laws. Some had religious freedom but most did not.
Maryland & Pennsylvania both wanted the port of Baltimore. There were families who wanted to live in MD because there was more religious freedom and the taxes were lower there than in PA. They lived in MD for over 10 years when William Penn brokered a deal with Lord Baltimore and these families ended up in PA.
1763 - 1780 Look in England's census records. Not in US census until 1790.
Florida reached all the way from present Florida to just a little East of Jackson Mississippi. Later MS was formed from a large chunk of FL to just East of Jackson MS. When MS attained US territory status, It reached from GA to LA (taking up part of FL and LA). When AL became a territory, it was carved out of MS Territory and the present state boundaries were established. So you could have a relative born in FL, lived in MS and died in MS or AL without him ever moving. Keep that in mind when checking census and other records.

1803 United States purchased Louisiana from France. Also shows that AL was not on the map where the Mississippi Territory is located.
Tennessee used to be a part of North Carolina. When TN attained statehood, a new boundary was established. Again someone could show up in each state and never move. IE the Cumberland River Settlement was in NC; but later became a part of TN.
1607-1776 South Carolina was part of the VA charter.
Before all the Colonies were established South Carolina was part of the Virginia Charter. After the Virginia Charter became South Carolina, the Waxhaw areas of North Carolina and South Carolina fought over the boundary there for centuries. The boundary flopped back and for so many times that your relative could have settled in NC but ended up in SC without ever moving. Not only that, if they lived or were born in the VA charter, they could have been born in VA, lived in NC and died in SC.
Virginia had a large section that became KY. Later, the North West corner of VA became W. VA.
1776 map of the United States.
After the Louisiana Purchase. In 1820 we have Louisiana, Alabama is finally on the map along with Florida, Tennessee, Indiana, Illinois & Missouri.
1820 map of the United States.
And then you have Alaska that was a part of Russia. Born in Russia and die in the United States without moving.

Purchased from Russia in 1867 as a territory and became a state in 1939
Texas as a Republic went from Mexico and encompassed Parts of what is today New Mexico, Oklahoma, Kansas, Colorado & Wyoming. When it became a state, the boundaries became where they are today. A person could have been born in Mexico, lived in TX and died in NM, WY, OK, KS or CO without ever moving.
1845 You will not find a US census with TX in it until 1850

Which country to look for according to the dates under the flag.
Louisiana went from the Gulf of Mexico all the way to Canada. A person could have been born in LA and died in AK, OK, MO, KS, CO, IO, IN, ND, SD, MN, WY or MT
The Hawaiian Islands were Polynesian (Asian) the Sandwich Islands (so named by Spain). They belonged to the British before becoming a US territory from 1783-1898. They became the Republic of Hawaii in 1898 and became a state on August 21, 1959. So if looking for ancestors, you could be looking at Polynesian, Spain, England, Republic of Hawaii, US territory or US citizen.


So somewhere around 1959 the states boundaries were finally set. It's important that you remember this when you are researching because you don't want to put where someone was born, lived and died in stone. Be flexible. You will know it's your ancestor if the dates, family members and location at that time match up.
If you are searching for Indian heritage, this map shows where the different tribes lived.
