WASHINGTON (AP) — Letters and diaries saved for 150 years from those who lived through the Civil War are offering a new glimpse of the arguments that split the nation.

The Library of Congress holds the largest collection of Civil War documents. It has pulled 200 items from its holdings for a new exhibit to reveal both private and public thoughts from dozens of famous and ordinary citizens who lived in the North and the South.

Robert E. Lee, for example, was grappling with divided federal and state allegiances. Ultimately, Lee believed his greater allegiance was to his native Virginia, as he wrote to a friend about resigning his U.S. Army commission.

Dozens of writings are featured in the new exhibit "The Civil War in America" at the library in Washington until June 2013.