The term First Lady originated in 1849, when U.S. President Zachary Taylor called Dolley Madison, wife of the fourth U.S. President James Madison, "First Lady" at her state funeral while reciting a eulogy written by himself.
Harriet Lane, niece of bachelor President James Buchanan was the first woman to be called First Lady while actually serving in that position. The phrase appeared in Frank Leslie's Illustrated Monthly in 1860, when he wrote, "The Lady of the White House, and by courtesy, the First Lady of the Land." Once Harriet Lane was called First Lady, the term was applied retrospectively to her predecessors.
The title first gained nationwide recognition in 1877, when Mary C. Ames wrote an article in the New York City newspaper The Independent describing the inauguration of President Rutherford B. Hayes. She used the term to describe his wife, Lucy Webb Hayes.