A display in the civil rights museum tells of the 1966 KKK firebombing of the Dahmer home outside Hattiesburg after Vernon Dahmer, the local NAACP leader, announced he would pay poll taxes for black people registering to vote.
These attacks, the statement claimed, disrespect the efforts of Fannie Lou Hamer, Aaron Henry, Medgar Evers, Robert Clark, James Chaney, Andrew Goodman, Michael Schwerner, and "countless others who have given their all for MS to be a better place".
The Mississippi Civil Rights Museum event will begin Saturday with a ribbon-cutting ceremony and will feature speeches from civil rights leaders, elected officials, and Mississippi Gov. Phil Bryant (R), who extended the invitation to President Trump.
The museum has been in construction since 2014, and is scheduled to open in Jackson, Mississippi on Saturday.
Derrick Johnson, the organization's president, said in a statement that Mr. Trump's record on "the protection and enforcement of civil rights have been abysmal and his attendance is an affront to the veterans of the civil rights movement".
This isn't the first time President Trump's presence at a museum has upset some African-Americans.
The White House said Trump hopes others will join him in recognizing "that the movement was about removing barriers and unifying Americans of all backgrounds". Bryant said the president's appearance brings importance to the event.
"We know that the work that we do is going to be in museums and on display not only through our generation but for all of the generations to come", said Spangler.
In the Mississippi Civil Rights Museum, columns list about 600 documented lynchings - a lot of them of black men. He was held at the infamous Mississippi State Penitentiary at Parchman.
The Georgia Democrat and civil rights icon helped organize the 1964 Freedom Summer targeting segregation in Mississippi.
"If God gives me the breath and the strength, I will address his attendance when I stand to speak", she told The New York Times. The Rev. C.J. Rhodes, a prominent African American clergyman, tweeted Thursday morning that Lewis' "voice is needed here now more than ever". A museum of Mississippi History covers 15,000 years of human habitation.
The Mississippi museum joins several others focused on civil rights: the Center for Civil and Human Rights in Atlanta; the National Civil Rights Museum in Memphis, Tennessee; the Rosa Parks Museum in Montgomery, Alabama; Birmingham Civil Rights Institute in Alabama.
The two distinct museums under a single roof are both funded by State tax dollars and private donations.