Harper Lee was considered a success as a writer in 1960 when her novel "To Kill a Mockingbird" was published. The book was an immediate critical and commercial success, quickly becoming a bestseller. In 1961, she won the Pulitzer Prize for Fiction for the novel, cementing her status as a successful and acclaimed writer. The novel remains a classic of American literature and has sold more than 40 million copies worldwide.

Key Points About Harper Lee's Success

• "To Kill a Mockingbird" was published on July 11, 1960, and quickly achieved bestseller status.
• The novel won the Pulitzer Prize for Fiction in 1961.
• The book was adapted into a highly successful film in 1962.
• Harper Lee's success was marked both critically and commercially early on, stemming from this novel.

Thus, Harper Lee's success as a writer was recognized primarily from 1960 onward following the publication and acclaim for "To Kill a Mockingbird."