Complex sentence: His major success as a writer came late in life, when the Aubrey-Maturin series caught the eye of an American publisher, drawing more readers and favourable reviews when the author was in his seventies.
Split into simpler sentences: His major success as a writer came late in life, when the Aubrey-Maturin series caught the eye of an American publisher. The series drew more readers and favourable reviews when the author was in his seventies.