Frederick Manfred (1912–1994), born Frederick Feikes Feikema VII, was a regional American novelist of Dutch Frisian heritage who wrote about the northern Plains. Over four decades he published about forty books, including the acclaimed frontier novel Lord Grizzly.

Willem Jacob Luyten (1899–1994) was a Dutch American astronomer at the University of Minnesota who became the leading authority on stellar proper motion, cataloging over 200,000 stars and discovering many nearby stars including the well-known Luyten’s Star.

Arie Luyendyk (born 1953) is a Dutch-American race car driver and two-time Indianapolis 500 champion, winning in 1990 and 1997. A former Formula Ford champion, he later competed successfully in IndyCar and major endurance races.

Shannon Lucid (born 1943) is an American astronaut and biochemist who flew on five NASA missions and spent 188 days aboard the Russian space station Mir in 1996, then a record for the longest spaceflight by a woman.

Jack R. Lousma (born 1936) is a U.S. Marine Corps aviator and NASA astronaut who flew on Skylab-3 in 1973 and commanded Space Shuttle Columbia’s STS-3 mission in 1982, logging over 1,600 hours in space.

Hendrik Willem van Loon (1882–1944) was a Dutch American historian, writer, and illustrator best known for The Story of Mankind, which won the 1922 Newbery Medal and made world history accessible to younger readers.

James Longstreet (1821–1904) was a senior Confederate general during the American Civil War and a principal commander under Robert E. Lee. After the war he served in several U.S. government posts and later wrote memoirs defending his wartime actions.

William Livingston (1723–1790) was a lawyer, patriot, and the first elected governor of New Jersey. A signer of the U.S. Constitution, he also served in the Continental Congress and supported the American cause during the Revolution.

Philip Livingston (1716–1778) was a New York merchant, political leader, and signer of the Declaration of Independence. A member of the prominent Livingston family, he served in the Continental Congress and helped support the American Revolution.

Norman F. Lent Jr. (1931–2012) was a Long Island congressman who served in the U.S. House from 1971 to 1993. A moderate Republican, he helped shape environmental legislation including the Superfund law and Clean Air Act amendments.

David Leestma (born 1949) is a Dutch American astronaut and U.S. Navy aviator who flew on three Space Shuttle missions between 1984 and 1992, later serving in senior NASA leadership roles overseeing astronaut operations and flight crew activities.

John Lansing Jr. (1754–1829) was a New York jurist and political leader who served in the Continental Congress and attended the Constitutional Convention of 1787. Though he declined to sign the Constitution, he later became Chief Justice and Chancellor of New York.