- For the Russian poet, see Ivan Pnin.
The book's eponymous protagonist, Timofey Pavlovich Pnin, is a Russian-born professor living in the United States. Pnin, a refugee in his 50s from both Communist Russia and what he calls the "Hitler war", is an assistant professor of Russian at fictional Waindell College, possibly modeled on Cornell University or Wellesley College, both being places where Nabokov himself taught. At Waindell, Pnin has settled down to an uncertain, untenured, but semi-respectable academic life, full of various tragicomic mishaps, misfortunes, and difficulties adjusting to American life and language.
Characters in the book include his departmental supervisor, various professors and university staff, his landlord, his ex-wife, and her son. The book's seemingly unreliable narrator identifies himself as one 'Vladimir Vladimirovich N---' and bears similarities to Nabokov himself, such as his interest in lepidoptery and his landed-gentry Russian émigré past.
At the end of the book, Pnin seems to be settling down and finding a sort of happiness. Unexpectedly, he loses his job and is last glimpsed fleeing Waindell College for an unknown destination.
The novel draws from Nabokov's experience at American academic institutions, primarily Cornell, and it has been claimed that it is "teeming" with people and physical details from that university. The main character is based, in part, on Cornell Professor Marc Szeftel, who may have "somewhat resented the resemblance".
Sections of Pnin were first published, in installments, in The New Yorker in order to generate income while Nabokov was scouring the United States for a publisher willing to publish Lolita. It was soon expanded, revised, and published in book form. 
- Lodge, David (2004). Introduction to Pnin. Everyman's Library. ISBN 1-4000-4198-8.
- Nabokov, Vladimir (2004). Pnin. Everyman's Library. p. 132. ISBN 1-4000-4198-8.
- Field, Andrew. VN, The Life and Art of Vladimir Nabokov. Crown Publishers, Inc., New York (1977), ISBN 0-517-56113-1.
- Lodge, page xi
- Lodge, David (8 May, 2004). "Exiles in a small world". The Guardian. Retrieved 9 April 2013.
- Galya Diment (1997). Pniniad: Vladimir Nabokov and Marc Szeftel. University of Washington Press. p. 58. ISBN 978-0-295-80108-7.