Portal:United States/Anniversaries/August/August 28
- 1830 – The Baltimore and Ohio Railroad's new Tom Thumb steam locomotive races a horse-drawn car, presaging steam's role in US railroading.
- 1862 – American Civil War: Second Battle of Bull Run, also known as the Battle of Second Manassas.
- 1867 – The United States takes possession of the, at this point unoccupied, Midway Atoll.
- 1955 – Black teenager Emmett Till is murdered in Mississippi, galvanizing the nascent American Civil Rights Movement.
- 1957 – U.S. Senator Strom Thurmond begins a filibuster to prevent the Senate from voting on Civil Rights Act of 1957; he stopped speaking 24 hours and 18 minutes later, the longest filibuster ever conducted by a single Senator.
- 1963 – Martin Luther King Jr. (pictured) delivers his I Have A Dream speech on the steps of the Lincoln Memorial to an audience of at least 250,000, during the March on Washington for Jobs and Freedom.