She graduated in 1919 in English and French from the newly established University College, Dublin, and she then moved to London, where she worked as a teacher for a year.

[4] In addition to novels, she wrote plays, film scripts, short stories, essays, copious journalism, two biographical studies, and two very personal travelogues.

[5] Even though Kate O'Brien lived outside of Ireland for most of her adult life, the country played a crucial role in her creative output.

O'Brien wrote a political travelogue, Farewell Spain, to gather support for the leftist cause in the Spanish Civil War, and it has been argued that she was close to anarchism in the 1930s.

Kate O'Brien's determination to encourage a greater understanding of sexual difference – several of her books include positive gay/lesbian characters —, make her a pioneer in queer literary representation.

Following a debate on the banning of The Land of Spices in the Irish senate, and a campaign supported by Seán Ó Faoláin and others, the censorship laws were somewhat reformed in 1946 by creating an Appeals Board.

[9] In the classic film Brief Encounter (1945), the co-protagonist Laura (Celia Johnson) says she has reserved "the new Kate O'Brien" at her local Boots library,[10] which prepares the audience for the moral dilemmas that the character is about to face.