Russian writer of innocent-sounding fables that satirized contemporary social types in the guise of beasts. His command of colloquial idiom brought a note of realism to Russian classical literature. Many of his aphorisms have become part of everyday Russian speech.

Born to an impoverished family, Krylov had little formal education and began to work as a clerk at the age of nine. While still in his teens he wrote operas, comedies, and tragedies. After 1789 he enjoyed some success as a satirical journalist until government censorship intervened. In 1805 he began translating the fables of Jean de La Fontaine but found that his true medium was writing fables of his own. The publication of his first book of fables in 1809 gained him the patronage of the imperial family and virtually an official sinecure—a post in the St. Petersburg public library—which Krylov maintained for 30 years. He produced eight additional books of fables, all written in verse, and received many honours.

Although some of his themes were borrowed from Aesop and La Fontaine, they altered in Krylov's hands. His foxes and crows, wolves and sheep, whether wise or foolish, were always recognizable Russian types. His salty, down-to-earth parables emphasized common sense, hard work, and love of justice and made him one of the first Russian writers to reach a broad audience.