President George W. Bush awards the Presidential Medal of Freedom to American novelist Harper Lee in the East Room of the White House, November 5, 2007.

Harper Lee, who wrote one of America's most beloved literary classics, "To Kill a Mockingbird," died at the age of 89 on Friday.

A statement from Tonja Carter, Lee's attorney in her hometown of Monroeville, Alabama, said Lee had "passed away early this morning in her sleep".

To Kill a Mockingbird" was published in 1960 as the civil rights movement was heating up and its unflinching examination of racial hatred in the South made it especially poignant. Its theme could be summed up with the advice that Atticus Finch, the noble lawyer, gave his young daughter, Scout: "You never really understand a person until you consider things from his point of view - until you climb into his skin and walk around in it.