He studied with E.F. Wenzel at the Leipzig Conservatory (1858-62), where he became intimately familiar with early Romantic music (especially Schumann's), gaining further experience in Copenhagen and encouragement from Niels Gade. Not until 1864-5 and his meeting with the Norwegian nationalist Rikard Nordraak did his stylistic breakthrough occur, notably in the folk-inspired Humoresker for piano op.6. Apart from promoting Norwegian music through concerts of his own works, he obtained pupils, became conductor of the Harmoniske Selskab, projected a Norwegian Academy of Music and helped found the Christiania Musikforening (1871), meanwhile composing his Piano Concerto (1868) and the important piano arrangements of 25 of Lindeman's folksongs (op.17, 1869). An operatic collaboration with Bjornson came to nothing, but his incidental music to Ibsen's Peer Gynt (1875), the most extensive and best known of his large compositions, produced some of his finest work. Despite chronic ill-health he continued to tour as a conductor and pianist and to execute commissions from his base at Troldhaugen (from 1885); he received numerous international honours. Among his later works, The Mountain Thrall op.32 for baritone, two horns and strings, the String Quartet in g Minor op.27, the popular neo-Baroque Holberg Suite (1884) and the Haugtussa song cycle op.67 (1895) are the most distinguished.
Grieg was first and foremost a lyrical composer; his op.33 Vinje settings, for example, encompass a wide range of emotional expression and atmospheric colour, and the ten opus numbers of Lyric Pieces for piano hold a wealth of characteristic mood-sketches. But he also was a pioneer, in the impressionistic uses of harmony and piano sonority in his late songs and in the dissonance treatment in the Slatter op.72, peasant fiddle-tunes arranged for piano.