Ida B. Wells , whose 153rd birthday would be on Thursday, was a prominent critic of lynchings in the late 19th century and early 20th century. And while black Americans likely knew at the time that the acts of terror were fairly common, it turns out we still don't know exactly how common they were while Wells was still alive.

A recent report by the Equal Justice Initiative found lynchings of African Americans by white communities in the South claimed nearly 4,000 lives between 1877 and 1950. That's 700 more lynchings than prior studies estimated, but that number likely doesn't account for all the deaths to the racist attacks.

EJI looked at the 12 states where lynching was most common: Alabama, Arkansas, Florida, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, Texas, and Virginia. Between these states, there were huge disparities in how often lynchings occurred.

Lynchings weren't typically carried out as a punishment for a crime. The report said, "Racial terror lynching was a tool used to enforce Jim Crow laws and racial segregation — a tactic for maintaining racial control by victimizing the entire African American community, not merely punishment of an alleged perpetrator for a crime."

Some examples:

In 1904, a white mob lynched General Lee, a black man, for knocking on the door of a white woman's house in Reevesville, South Carolina.

In 1916, white men in Cedarbluff, Mississippi, lynched Jeff Brown because he accidentally bumped into a white girl while running to catch a train.

In 1919, a white mob in Blakely, Georgia, lynched William Little for refusing to take off his army uniform after returning from World War I.

These acts had a deep impact on Southern governance and culture. Many blacks left the South out of fear that they could be the next victims of lynchings. Those who remained in the region were oppressed by Jim Crow laws that imposed segregation — and many were afraid to speak out due to concerns for their lives.

In the dozen of states studied by the organization, EJI noted that there was "an astonishing absence of any effort to acknowledge, discuss, or address lynching." Many of these places have erected monuments memorializing Confederate, Southern, and civil rights leaders, but they've rarely paid similar tribute to victims of lynchings.

As EJI points out, it's impossible to address racial inequality in America without first acknowledging one of the many ways blacks were oppressed for generations. Without an understanding of lynchings and other acts of terror directed at black Americans, the depth of systemic racism during the era of Jim Crow and segregation can never be fully understood.

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