Pres. Joe Biden signed into law Thu. a bill designating June 19th—AKA Juneteenth—an official federal holiday.

June 19th marks the day in 1865 when enslaved people in Texas were emancipated from slavery. (WaPo)

Juneteenth is now the U.S.'s 12th national holiday, and the first new federal holiday since MLK Jr. Day in 1983. (CNN)

Legislation to make Juneteenth a federal holiday passed both chambers of Congress this week.

The bill passed the Senate by unanimous consent on Tue.. The House voted to pass the bill by a 415-14 vote Wed.. (WaPo)

Biden and Vice President Kamala Harris delivered remarks Thu. before signing the bill into law.

Harris: "Today is a day of celebration."

Thu.'s signing was the culmination of a years-long effort by legislators and activists to make the day a federal holiday.

In 2016. then-89 year old Opal Lee began a 2.5-mile annual walk in Texas to make Juneteenth a national holiday. (CNN)

Lee told ABC7, "Surely somebody would notice a little old lady in tennis shoes."

In 2020, Rep. Sheila Jackson Lee introduced a bill to make June 19 a federal holiday—an effort that failed in the Senate.

Lee and Sen. Ed Markey reintroduced their Juneteenth bills this year, passing both with broad bipartisan support. (CNN)

Biden: "In short, this day doesn’t just celebrate the past. It calls for action today."

CNBC: "Most federal workers will observe Juneteenth on Friday this year because June 19 falls on a Saturday."