What Is 'Juneteenth' And Tulsa Massacre? Trump Slammed For Holding Rally On Holiday

June remains a month of both great jubilation and unparalleled sorrow for African-Americans. And considering the importance of June to the psyche of African-Americans, black leaders are aghast as to why President Donald Trump chose to hold his first campaign rally in three months at Tulsa -- of all places -- and on Juneteenth no less.

First the history. It's the month of "Juneteenth" -- or June 19 -- marking the end of slavery in the United States in 1865. Also known as Emancipation Day, Juneteenth commemorates the date when Maj. Gen. Gordon Granger, a Union Army general, arrived at Galveston, Texas, to inform residents President Abraham Lincoln had freed the slaves.

He also ordered slave owners to comply with the Emancipation Proclamation issued Jan. 1, 1863. Texas was the last Confederate State where the Emancipation Proclamation was announced.

June is also the month of the horrific "Tulsa Race Massacre" from May 31 to June 1, 1921 when mobs of white residents attacked black residents and businesses of the Greenwood District in Tulsa, Oklahoma.

As many as 200 blacks were murdered in the massacre at Greenwood, which at the time was the wealthiest black neighborhood in the U.S. Greenwood was also known as the "Black Wall Street" because of its affluence. The Tulsa Massacre is considered "the single worst incident of racial violence in American history."

Some African-American activists say Trump is deliberately insulting blacks and showing his favor for white supremacists.

Sen. Kamala Harris, D-CA, fiercely assailed Trump's decision to hold the rally at Tulsa on Juneteenth.

"This isn't just a wink to white supremacists -- he's throwing them a welcome home party," she tweeted Thursday.

Harris, a leading contender to become Joe Biden's running mate, has long criticized Trump as racist. She's often said Trump is unfit to be president because he doesn't understand the racial turmoil engulfing the country.

Rep. Al Green, D-TX, a member of the Congressional Black Caucus, tweeted Thursday that Trump holding the rally in Tulsa was "overt racism from the highest office in the land."

Alicia Andrews, chair of the Oklahoma Democratic Party, said Trump is "thumbing his nose at the real issue of racial inequity."

"There's a man's words, and then there are his actions," she said. "Him coming here on that date, without making any outreach to the community, and saying it's for unity. It is a slap in the face."

Mechelle Brown, program coordinator and tour guide for the Greenwood Cultural Center in Tulsa, said the black community doesn't feel Trump is genuinely interested in the history of the Greenwood district.

Brown said Trump's visit to Tulsa "during Juneteenth, as we are commemorating the 99-year anniversary of the massacre, is insulting."

Trump's campaign said the timing and location of the rally were deliberate. It said Trump sees the rally a chance to tout his alleged "record of success for black Americans."