It's no secret Joe DiMaggio loved Marilyn Monroe. The baseball great cried at her funeral and for 20 years had flowers placed at her crypt several times a week.

The public displays were unusual for the famously stoic and private DiMaggio. Now, his heartbreak over the breakup of their marriage will get a rare public airing when "Marilyn Monroe's Lost Archives" goes up for bid at Julien's Auctions in Beverly Hills next month.

"I love you and want to be with you," DiMaggio said in one pained letter to Monroe from the collection, written when she announced she was filing for divorce after a matter of months in 1954. "There is nothing I would like better than to restore your confidence in me."

The 300 items also include love letters from Monroe's third and final husband, playwright Arthur Miller. There's also a handwritten letter from Monroe to Miller in which the woman who was arguably Hollywood's greatest sex symbol muses about her many insecurities.

DiMaggio wrote in his letter that he learned Monroe was leaving him when he saw her make the announcement on television.

"My heart split even wider seeing you cry in front of all these people," he wrote in the letter addressed to "Mrs. Joe DiMaggio" and mailed special delivery.

Other letters in the collection come from such friends as Clark Gable, Cary Grant and Jane Russell, the latter imploring Monroe in 10 neatly handwritten pages to give her marriage to DiMaggio another chance.

"It really gives you the chills when you read some of the stuff and see the intimacy and the personal nature of it," said auction curator Martin Nolan, who spent nine months organizing and cataloging the collection.

Auction owner Darren Julien estimates the pieces could fetch $1 million or more, noting a watercolor Monroe painted and planned to give to President John Kennedy went for $80,000 at an estate auction nine years ago. Monroe's "collectability" has skyrocketed in recent years, driven in part by deep-pocketed Asian and European collectors with a fondness for American pop-culture artifacts, he said.

The fact that the centerpiece of this collection is not just celebrity tchotchkes but deeply personal artifacts is also expected to fuel interest.

"We anticipate a lot of fans will be here. They'll fly in from all over the world," said Julien, who will put the items on display to the public at his Beverly Hills gallery for four days before they go on the block Dec. 5-6.

Monroe, who died of a drug overdose at age 36 in 1962, willed "The Lost Archives" to her mentor, the legendary acting coach Lee Strasberg. He gave it to a friend he trusted would take proper care.

That friend's family, which Julien said wants to remain anonymous, obviously met Strasberg's expectations. Many of the letters look as pristine as the day their authors wrote them.

"Please, if I've ever made you cry or made you even more sadder, ever for a second, please forgive me, my perfect girl. I love you," Miller wrote in a pencil-scribbled P.S. at the bottom of a typewritten letter.

In a reply to one of his missives, Monroe takes issue with what the author of "Death of a Salesman" had called her nobility in handling a difficult childhood followed by public adulation that nearly crushed her.

"In other words, there was no choice to make, the same road was always before me," she wrote. "So for you to speak of my nobility, it really wasn't so noble."

She went on to say: "It's doubly difficult to understand that you, the most different, most beautiful human being, chose me to love."

Other items in the collection include a 19-minute reel of a movie made for Monroe after her final picture, 1961's "The Misfits," wrapped. It shows her frolicking happily at the beach with co-star Gable and others.

Notably, there's also a framed letter she kept on her coffee table from costume designer Cecil Beaton, who assured her she really was a fine actress.

"It's fantastic to see how loved she was," Nolan said. "Like you thought she was vulnerable and not loved and she craved love and she needed that reassurance. But she had it. She had it with Joe DiMaggio. She had it with Arthur Miller."

And, so it seems, she still has it with much of the rest of the world.