Nica grew up with the kind of wealth that most people can't really picture — the Rothschild banking family, English branch, country houses and all of it. She married a French baron, had five kids, and was living the life her background had arranged for her. Then she heard jazz, specifically bebop, and something cracked open. By the early 1950s she had left her husband, moved to New York, and started spending her nights at the clubs where Thelonious Monk, Charlie Parker, Bud Powell, and their peers were working.

What she actually did for these musicians is harder to reduce than people sometimes make it. Yes, she lent money — she was one of the few people in their orbit who had any. But she also just showed up, night after night, in a silver Bentley that became a kind of running joke and landmark. She wrote down the wishes of dozens of musicians — a project she called the "Three Wishes" interviews, where she asked jazz players what they would want if they could have anything. The results, eventually published as a book, are funny and moving and completely unlike any formal oral history.

The Charlie Parker situation is the one most people know about. Parker collapsed and died in her suite at the Stanhope Hotel in 1955. The tabloids had a field day. Nica's name was dragged through the gossip columns and her reputation took a beating she largely ignored. She lost her cabaret card — the license required to perform or even sit in at New York jazz clubs — not because she had done anything wrong but because the authorities found her association with musicians suspicious. She fought it and eventually got it back.

Thelonious Monk is the relationship that defined the last decades of her life. She was devoted to him for years, and after his health declined she took him in at her home in Weehawken, New Jersey — a house she called the Cathouse for the dozens of cats she kept. Monk lived there until his death in 1982. There is genuine debate about whether her protectiveness served him well in his final years when he had largely stopped playing, but her commitment was not in question. She had made her choice about what mattered to her a long time before.

Nica was not a musician and did not pretend to be. She was a listener who took the music seriously enough to reorganize her entire life around it. That's unusual in any era. The jazz world has always had patrons and hangers-on, but most of them kept a comfortable distance. She didn't. She was in the room, at the table, on the road. Monk wrote "Pannonica" for her. Kenny Clarke and Barry Harris both wrote pieces with her name on them. When musicians write tunes for you, it usually means you were actually there.