Great Depression
- League of United Latin American Citizens
- Ledbetter, Huddie [Lead Belly]
- Lenz, Louis
- Lerma, Everardo Carlos [E. C.]
- LeRoy, Moses
- LH7 Ranch
- Light Crust Doughboys
- Limberg, Emilie Josephine
- Little Mexico
- Lomax, John Avery
- Long, Emma Pauline Jackson
- Long, Huey
- Lovett, Edgar Odell
- Lower Colorado River Authority
- Lower Neches Valley Authority
- Lozano, Ignacio E.
- Lozano, Vicente, Sr.
- Lynching
- Machuca, Esther Nieto
- Mackey, James Raleigh [Biz]
- Magnolia Park, TX
- Mahon, George Herman
- Malone, Clarence M., Sr.
- Mansfield, Joseph Jefferson
- Marin, Eulalio
- Martinez, Celia Mireles
- Maverick, Fontaine Maury
- McAuliffe, Leon
- McCarthy, Glenn Herbert
- McClendon, James Wooten
- McCormick, George, Jr.
- McDavid, Percy H.
- McElroy, George Albert
- McNay, Jessie Marion Koogler
- Memorial Healthcare System
- Mendoza, Lydia
- Menezes, Sarah Eleanor Cory
- Merchants and Planters Oil Company
- Methodist Hospital of Houston
- Mexican Americans and Repatriation
- Meyer, Leopold Leopold
- Miller Outdoor Theatre
- Miller, Henry Pomeroy [Roy]
- Miller, W. Henry
- Mims, Henry Lucius
- Moody, Daniel James, Jr.
- Moore, Edward Weaver
- Moore, Frederick Douglas
- Morse, Robert Emmett
- Mount Tabor Indian Community