The art collection of David and Peggy Rockefeller, which is being up for sale by Christie’s, is being projected to be the biggest, by dollar value, of all time.

A Christie’s auctioneer has cited that the collection could go for north of $500 million. The earnings from the auction are all set to go to charity.

This development is an intriguing one especially for a collection, the roots of which began with an insult that involved the Rockefellers’ alleged lack of taste in art.

The collection was owned by billionaire philanthropist and former Chase Manhattan chief, David Rockefeller, who passed away around a year ago at 101, and his late wife.

As the grandson of John D. Rockefeller, the Gilded Age industrialist who co-founded Standard Oil Company, David Rockefeller had been raised with masterpieces all around him. However, he wasn’t as keen about collecting anything but beetles until a time came when he was shamed into it.

Shortly after being elected to the board of the Museum of Modern Art in 1948, Marga Barr, the wife of the museum’s first director, Alfred Barr, asked the Rockefellers why they possessed so many paintings of “little men in red coats” at their residence on Manhattan’s Upper East Side, criticizing the unremarkable 18th century British paintings of fox hunting, equestrian scenes and British officers she witnessed during a visit there.

“Peggy and I were taken aback by her bluntness and more than a little annoyed but, upon reflection, had to admit the art on our walls wasn’t of great calibre,” wrote Rockefeller in his memoir. “We decided then and there to place more emphasis on quality in our purchases.”

The Barrs went on to teach them about late 19th century and early 20th century art, and pointed them in the right direction they slowly built their collection of Impressionist and modern art, which was collected in the late 1940s through the early 1960s. In a piece about moguls purchasing art in the April 1960 issue of Fortune, he said, “Business should support the art of today as the Medici of Florence did.”

It wasn’t before long that the Rockefellers had become adept at collecting expensive and well-known art pieces.

In 1958, they acquired one of the paintings that is part of this week’s sale: the Henri Matisse’s Odalisque couchée aux magnolias, that was painted in Nice, France, in 1923. The Rockefellers bought it from a Chicago modernist art collector named Leigh Block. Now, Christie’s deems it as “the most important work by the artist to be offered on the market in a generation.” Believed to have a value of around $70 million, it’s also the highest estimated work by Matisse to be offered at an auction.

According to Peter J. Johnson, the family historian who helped Rockefeller pen his memoir, the post-war period was an ideal time to begin collecting.

“A lot of art was starting to become available and quite frankly it’s because many of the people who had owned this art in Great Britain or France were still recovering from the war, and the one thing that they had that was liquid were paintings,” Johnson said. “Often times they made these things available and these things began to move into American collections.”