These amazing charts were created to show where people came from before they moved to the state where they live now. In each state you can see the trail of where majority of the people came from before they moved there.
These charts show how the heritage and racial profile of each state was created over a period of time. They provide evidence to show where people are most likely to come from and why that might be. Events in history, natural events in nature, and even economic conditions cause changes in where people live. Many times people go and live near those they know such as extended family members and some go where the jobs are located.
The nice thing about these charts is that they are interactive and will tell you more about the makeup of each state at any given time since 1900. If you study them carefully and view the states that are next to each one as a group you begin to see migration patterns in how people move around the country. This is interesting to know for many reasons but, depending on how well one knows the history of events taking place in their state and the country you also see the bigger picture of why people might move around.
If you are interested in learning more about census data you can visit the IPUMS website and see other types of data sets and charts they have created.