Former President Barack Obama’s private foundation announced on Monday that it had been promised a donation of $100 million from the Amazon founder Jeff Bezos.

The gift, the largest yet for the Obama Foundation, was one in a series of splashy donations by Mr. Bezos, one of the world’s richest men, in recent months. Last week, Mr. Bezos announced $96.2 million in grants to groups working to end family homelessness.

Since stepping down as chief executive of Amazon in July, Mr. Bezos has significantly raised his profile as a philanthropist, in addition to traveling to space on a ship made by his rocket company, Blue Origin.

In return for the donation, Mr. Bezos asked that a plaza at the Obama Presidential Center be named for the civil rights leader John Lewis, who died last year. The foundation broke ground on the center, which will include Mr. Obama’s presidential library, a museum, an athletic center and more, earlier this year.

“Freedom fighters deserve a special place in the pantheon of heroes, and I can’t think of a more fitting person to honor with this gift than John Lewis, a great American leader and a man of extraordinary decency and courage,” Mr. Bezos said in a statement released by the Obama Foundation. “I’m thrilled to support President and Mrs. Obama and their foundation in its mission to train and inspire tomorrow’s leaders.”

News of the gift was earlier reported by the online news group Puck.

It was neither Mr. Bezos’s biggest gift in recent months nor his first brush with Mr. Obama’s orbit. In September, Mr. Bezos, standing alongside John Kerry, Mr. Obama’s former Secretary of State, pledged $1 billion through his Bezos Earth Fund for conservation.