Secretary of State Antony Blinken announced earlier this week that the agency would display the flag to close out Pride Month, describing it as "a symbol that encompasses the diversity and intersectionality of LGBTQI persons and communities around the world."
There was a flag-raising ceremony at the State Department on Friday with remarks from Deputy Secretary of State Wendy Sherman, Chief Diversity and Inclusion Officer Ambassador Gina Abercrombie-Winstanley and glifaa president Jeff Anderson to mark the moment, according to an agency release.
I was honored to speak today as the progress flag was raised over @StateDept headquarters for the first time—demonstrating to people everywhere that the United States is committed to fighting for LGBTQI+ rights at home and abroad. #PrideMonth2021 pic.twitter.com/JnMkatH0Iq— Wendy R. Sherman (@DeputySecState) June 25, 2021
Anderson's organization, glifaa, represents lesbian, gay, bisexual, and transgender personnel at the State Department and other foreign affairs agencies.
The Progress flag builds on the six-stripe rainbow of the Pride flag by adding a chevron of white, pink, light blue, brown and black -- to symbolize transgender rights, people of color and those living with or lost to HIV/AIDS.
During an event at the Atlantic Council on issues facing the global LGBTQI community on Monday, Blinken explained the timing of the display "marks a couple of important turning points in our history for LGBTQI rights."
The flag started flying Saturday, June 26, on the anniversary of the 2015 Supreme Court decision in Obergefell v. Hodges, which established the fundamental right to same-sex marriage nationwide, through Monday, June 28, which marks the 52nd anniversary of the Stonewall Uprising of 1969.
"This is, again, the strength, the power of our own example, the willingness to speak up, to speak out to, show the strength of our own diversity, including at our embassies, I think sends a hugely important message," Blinken said.
Earlier this year, Blinken authorized U.S. embassies and consulates to fly the Pride flag on their official flagpoles, as was done under the Obama administration but revoked under Blinken's predecessor, then-Secretary of State Mike Pompeo, a conservative Republican. Under the Trump administration, posts were barred from flying any flag other than the U.S. flag on official flagpoles and had to seek permission to fly the Pride flag, which was denied to several embassies.
Then-Vice President Mike Pence said in 2019, "When it comes to the American flagpole, and American embassies and capitals around the world, one American flag flies."
When the Biden administration rescinded the policy in April, posts were, instead, given "blanket written authorization ... to display the Pride flag on the external-facing flagpole, for the duration of the 2021 Pride season," according to an internal State Department cable obtained by ABC News.
Even with the Progress flag flying high at home, for some, the gesture highlights progress still to be made.
Sachel Pemberton, a transgender Army veteran who served for nearly a decade under the "Don't Ask, Don't Tell" policy, told ABC News that the Biden administration needs to do more on federal protections for the LGBTQI community as, he argued, anti-transgender laws sweep through state legislatures at an alarming rate.
"I am proud that our leadership is taking steps, albeit baby steps, to recognize our community, but I'd rather see legislation happening than a flag flying over a building," he said.
According to Chase Strangio, deputy director for transgender justice at the American Civil Liberties Union, more anti-transgender bills have become law in 2021 than in the previous ten years combined.
"There needs to be stronger legislation of protection at the federal level," Pemberton added.
Blinken said Monday the U.S. this week sponsored its first-ever side event at the United Nations on the rights of transgender and gender diverse people around the world -- calling transgender rights a "core human rights issue."
"This is a core human rights issue, and we believe the United States belongs at the forefront of the fight -- speaking out, standing up for our values," he said.
He also said the Biden administration will make a "broader" announcement beyond the State Department soon that sends a "very clear, very strong message" that it wants "a workforce of talented people that reflect the true diversity of our country."
It all comes on the heels of another Biden administration policy shift -- although one that could take years to play out.
The Department of Veterans Affairs announced last weekend it plans to offer gender-affirming surgery to transgender veterans, with VA Secretary Denis McDonough saying the policy to ensure "equitable treatment and safety" of the population has been "deserved for a long time."
Last month, U.S. embassies around the world displayed Black Lives Matter flags to mark the anniversary of the murder of George Floyd by former Minneapolis police officer Derek Chauvin.
ABC News' Conor Finnegan contributed to this report.