Owen Thomas Edgar (June 17, 1831 – September 3, 1929) was, according to data from the United States Department of Veterans Affairs, the longest surviving U.S. veteran of the Mexican–American War.

Edgar saw service on the frigates Potomac, Allegheny, Pennsylvania and Experience.

[4] After the war, he worked at the Bureau of Engraving and Printing for twenty-one years, then worked at a bank for another thirty-one years.

He spent his final ten years living at the John Dickson Home in Washington, D.C.[5] He became the last surviving American veteran of the Mexican-American War on June 17, 1929 when fellow war veteran William Buckner died at the age of 101 in Paris, Missouri.

[6][7] Edgar died September 3, 1929, at the age of 98 after suffering a fall from a chair that fractured his leg, and was buried in Washington's Congressional Cemetery.