Eliza Eichelberger Ridgely (February 10, 1803 – December 20, 1867) was an American heiress, traveler, arbiter of fashion, and mistress of Hampton, the Ridgely plantation north of Towson, Maryland. She is the Lady with a Harp of Thomas Sully's portrait, now in the National Gallery of Art, Washington, D.C.
Eliza Ridgely was the only child of Nicholas Greenbury Ridgely (1770–1829), a rich wine merchant of Baltimore, who married her mother, Elisabeth Eichelberger, on July 30, 1801. Elizabeth had been born on December 6, 1783, at Baltimore, the daughter of Johann Martin Eichelberger and his wife Elizabeth Welsh, and died on February 10, 1803, aged nineteen years and two months, a few hours after the birth of her only daughter. Nicholas Ridgely died in 1829 and is buried in the cemetery at Hampton.
Eliza Ridgely was an heiress who became a foreign traveler and an arbiter of fashion. She met and befriended the Marquis de Lafayette during his United States tour of 1824–1825 and stayed in contact with him for the rest of his life. Some of his letters to her have survived, including an invitation to visit La Grange, his country estate in France—a visit which took place in 1834—and his congratulations on her marriage.
On January 8, 1828, Eliza Ridgely married John Carnan Ridgely (1790–1867). He was the son of Charles Carnan Ridgely of Hampton Mansion, and his father had served as Governor of the state of Maryland from 1815 to 1818.
John Carnan Ridgely was the grandson of John Carnan who married Achsah Ridgely. Achsah's brother, Charles Ridgely III (d. 1790), the builder of the Hampton plantation being childless as his end neared, willed that his sister's progeny should take the Ridgely name to inherit his vast estates. Thus, John Carnan Ridgely was, in fact, a fifth cousin of Eliza Eichelberger Ridgely.