Former President Barack Obama joined a group of notable athletes and activists in tipping his cap to honor the 100-year anniversary of the founding of baseball’s Negro Leagues.

The Tip Your Cap campaign launched online Monday with photos and videos from sports legends Hank Aaron, Derek Jeter, Michael Jordan, and the family of Jackie Robinson. Former U.S. presidents Bill Clinton, George W. Bush and Jimmy Carter also participated.

The tributes honored some of the Negro Leagues’ notable stars including Robinson, Satchel Paige, Byron Johnson, Willie Mays, Hank Aaron, and Ernie Banks. Robinson started his career with the Kansas City Monarchs and went on to break the color barrier in the major leagues with the Brooklyn Dodgers in 1947. Not long after, with many of its best players gradually following Robinson’s path, the Negro Leagues ceased operations.

“Today, I’m tipping my hat to everybody in the Negro Leagues who left a century-long legacy of talent and spirit and dignity in our country,” Obama said. “So, here’s to Satchel Paige, Josh Gibson, Cool Papa Bell and everybody else, including three brave women who did us all proud.”

Rockets general manager Daryl Morey also tipped his cap to the 100-year anniversary baseball’s Negro Leagues.

The campaign, which is being directed by Negro Leagues Baseball Museum President Bob Kendrick, moved online when centennial events planned to take place in major league stadiums this summer were canceled due to COVID-19.