Baroness Kathleen Annie Pannonica 'Nica' de Koenigswarter (née Rothschild; 10 December 1913 – 30 November 1988) was a British-born jazz patron, photographer and writer.

[3] In 1958, she purchased a house in Weehawken, New Jersey with a Manhattan skyline view, originally built for film director Josef von Sternberg.

The war imposed a suspension of her marital and family duties but she managed to send her children from France to America, secretly moving across continents.

[3] In New York, de Koenigswarter became a friend and patron of leading jazz musicians, hosting jam sessions in her hotel suite, often driving them in her Bentley when they needed a lift to gigs,[3] as well as sometimes helping them to pay rent, buy groceries, and making hospital visits.

[5] She was a regular visitor to many of New York's jazz clubs, including the Five Spot Café, Village Vanguard, and Birdland.

The club owner refused to give Art Blakey any money because the band had started late several times and we hadn't drawn a crowd.

She'd give money to anyone who was broke, bring bags of groceries to their families, help them get their cabaret cards, which you needed to work in New York.

This bitch was so rich she had permanent tables reserved at all the clubs and a number you could call from anywhere in New York to get a private cab.

There was no jive about her, and if you were for real you were accepted and were her friend.After Monk ended his public performances in the mid-1970s, he retired to de Koenigswarter's house in Weehawken, New Jersey, where he died in 1982.

[3] She used her wealth to pay for the funerals and burial grounds for several jazz musician friends, including Bud Powell, Sonny Clark and Coleman Hawkins.

[7]: 253  The San Francisco art rock band Oxbow released a recording entitled "Pannonica" (unrelated to the Thelonious Monk composition) with reissues of their 1991 album King of the Jews.

[11] De Koenigswarter (Nica) appears prominently in "El perseguidor", a one-hundred page story by Julio Cortázar in the book Las armas secretas (The Secret Weapons, 1959).

The book was edited for publication by Nadine de Koenigswarter, whom Nica always introduced to people as her granddaughter but who was in fact her great-niece.

In the Eastwood-produced documentary film Thelonious Monk: Straight, No Chaser (1988) she is seen in library footage and heard in an interview.