"Soeur (Sister) Angèle must have been the first nun-detective in fiction. She is a Sister of Charity (an order, we are told, founded by Vincent de Paul) but is also a medical doctor, attached at first to the French hospital and orphanage in Bethlehem, although we never see her there. She had previously been Dr Angèle Persent d'Ericy, before she had decided to become a nun. "She was of medium height .... Her face, freckled and lit up by two sparkling humorous eyes, was attractive. It fairly radiated intelligence and good will. She held herself very straight .... You knew that she was both kind and intelligent". She has "a sort of evangelical candour and purity of motive" and "an incurable idealisation of the moral quality of other people". Or, as her old professor put it, "You're still the same self-opinionated little devil" She nearly always carries "a large black bag ("there seemed nothing her enormous bag did not contain") and an immense umbrella" - although, by the second book, the color of the bag and umbrella seems to have changed to slate blue to match her habit.
She was created by the French author Henri (Henry in the English editions) Catalan whose real name was Henri Dupuy-Mazuel (1885 - 1962), who was the author of numerous novels, short stories and screenplays for silent films, and producer of the film Le Tournoi (The Tournament) that was directed by Jean Renoir in 1929. He used the pseudonym Henry Catalan for his Soeur Angèle novels."
At least three of Catalan's "Soeur Angele" detective stories were published in English. Both French and English editions are long out of print, but are easily available from sites like Advanced Book Exchange.
From the website: "Clerical Detectives: