The fireworks lighting up the sky over Lagoon Pond and Vineyard Haven Harbor Saturday night weren’t an early Fourth of July display — they were a fitting finale to the Evening of Discovery gala at the Martha’s Vineyard Museum.

The pyrotechnics capped a party that drew more than 500 people to the museum’s new location on Lagoon Pond Road, where they sipped champagne, explored the exhibits, took in the panoramic view of Vineyard Haven and Oak Bluffs and gathered for dinner under the tent.

During the surf and turf meal of lobster and beef, partygoers applauded speeches by museum director Phil Wallis, broadcaster Michele Norris and American historian David McCullough.

“He was an early believer in the idea that this museum needed a new home,” Ms. Norris said as she introduced Mr. McCullough as “a gifted storyteller [with] a great sense of history and a beautiful sense of history.”

“Well, I told her to exaggerate, and she has not disappointed,” Mr. McCullough joked as he took the podium.

The historian began his speech by announcing that he and his wife Rosalee have a new great-grandson.

“He will now represent the seventh generation of Rosalee’s family, the Barnes, to be on Martha’s Vineyard,” Mr. McCullough continued, as his listeners clapped and cheered. “I married up,” he continued, and the applause turned to hearty laughter.

Mr. McCullough then turned his attention to the audience members themselves, congratulating museum supporters for what the organization has accomplished.

“Very seldom is anything of consequence ever accomplished alone,” he said. “It’s a joint effort.

“If you wanted an example of a joint effort really pulling it off, you can see it right here tonight,” Mr. McCullough continued.

“Look what you’ve all done. It’s phenomenal.”

The museum has been open since early this year, but Saturday’s gala was the time for both year-round and seasonal supporters to celebrate both its new location, in the restored 1895 Mariners Hospital in Vineyard Haven, and the progress the organization has made over the past few years.

Founded in 1922 as the Dukes County Historical Society, the nonprofit changed its name to the Martha’s Vineyard Historical Society in 1996 and to the Martha’s Vineyard Museum in 2006.

Outgrowing its home in the 1740 Thomas Cooke House on an Edgartown side street, the museum purchased the old hospital in 2011 and, following a $31 million capital campaign, began renovations with the goal of opening the museum in late 2018.

Just a few months behind schedule, the new museum quietly opened its doors in March and is now open to the public Tuesday through Sunday beginning at 10 a.m.

Tuesdays from 5 p.m. to 8 p.m., museum admission is free, underwritten by local businesses. Wednesday through Sunday, closing time is 5 p.m. The museum café closes at 3 p.m. and the museum is closed on major holidays.

For more information about the museum and current exhibitions, visit mvmuseum.org.