Former ABC news anchor Carole Simpson has made, in her words, thousands and thousands of speeches, so she knew she wanted to do something special on Saturday to really engage those Vineyarders and visitors gathered at Deon’s Restaurant in Oak Bluffs to commemorate Juneteenth, the 145th anniversary of the end of slavery in the United States.

So as Ms. Simpson spoke of the holiday’s roots and importance, she went through three costume changes.

Dancing at Deon’s for Juneteenth, commemorating end of slavery. — Ivy Ashe

“I thought my transformation from a modern African-American woman to a slave and then to a freed slave would make it interesting,” she said of her decision to dress in different period clothes.

Ms. Simpson is currently journalist-in-residence with the Museum of African-American History in Boston.

“I’d never done anything like this before,” she said, “but I’m really pleased with the reaction. People said it was really enjoyable.”

Joshua, Tolu, Charles and Julia Bradley of Oak Bluffs. — Ivy Ashe

In between Ms. Simpson’s final metamorphosis, Martha’s Vineyard Regional High School student Grant Meacham delivered Frederick Douglass’s 1852 Fourth of July remarks, to thunderous applause. Event organizer Ardell Otten asked Mr. Meacham to read the speech, in which Mr. Douglass addresses the hypocrisy of asking a former slave to speak about the American independence movement.

“I thought it would be perfect for a young person to speak the words of Frederick Douglass,” Mrs. Otten said after the event, noting that Juneteenth is a “celebration of the success that has been achieved in spite of the past.”

Ms. Simpson agreed.

“Our history is important, and we should celebrate it — we should not be ashamed of the days of slavery. We overcame and we survived, and we’re here today standing toe-to-toe with white Americans who did not have the disadvantages we had, so I’m proud of it.”

Juneteenth commemorates June 19, 1865, two and a half years after the Emancipation Proclamation was signed, when word was brought to the residents of Galveston, Tex., that the Civil War had come to an end and the slaves had been freed. Texas was the last Confederate state to learn of the Proclamation, and observation of the Juneteenth events began in the state the next year. Now 36 states, including Massachusetts, mark Juneteenth as a state holiday or observance, although the day is perhaps best known in the area where it began.

Carole Simpson in one of her three guises. — Ivy Ashe

“I’m writing a letter to Obama — this should be a national holiday,” said Mary Louise Koch of Vineyard Haven. “I think we should honor everybody in this country.”

Proceeds raised during the Juneteenth event benefitted the Bradley Square Project, a collaboration between the Vineyard NAACP chapter and the Island Affordable Housing Fund.

The project seeks to restore Bradley Memorial Church, the Island’s first African-American place of worship. A portion of Saturday revenues from Circuit avenue merchants, including host venue Deon’s Restaurant, C’est La Vie and Cousen Rose Gallery, were also donated to the cause.