If you are looking for an excellent primer on the use of incarceration in the United States, you need to read this. "Over the last three decades of the 20th century, the United States engaged in an unprecedented prison-building boom that has given our nation the highest incarceration rate in the world. Among people with experience in criminal justice policy matters, the “hockey stick curve” of the national incarceration rate is well known; but until now more detailed data on the incarceration rates for individual states has been harder to come by. This briefing fills the gap with a series of more than 100 graphs showing prison growth (and sometimes decline) for every state in the nation to encourage states to confront how their criminal policy choices undermine our national welfare." The webpage explains with text and easily understood graphics: state policies that drive mass incarceration; what's the critical difference between incarceration rates and incarceration numbers; state prison incarceration rates for select states and overall; and state prison incarceration states by region (greater use to least)—south, west, midwest, and northeast.
This brief refers to the "50 State Incarceration Profiles" interactive map which is a great resource for seeing how the incarceration rate has grown over time and what racial disparities exist for each state.