Chester Alan Arthur was a Stalwart and the the 21st President of the United States. What counts him as a hero was that before he was even Vice-President to Half-Breed James A. Garfield, while he was a lawyer then, he defended a black woman named Elizabeth Jennings Graham, who was thrown off a whites-only streetcar in 1854. The next year, he won the case and led to the desegregation of New York trolleys. Arthur also holds the record as the last President not to have a Vice-President of his own, and not to have a First Lady (as his wife, Ellen Lewis Herndon died one year before his presidency, causing the First Lady position to be acted out by his sister instead), and absolutely, the only President to have neither.
In 1855, when he was not yet president, Chester defended a black woman named Elizabeth Jennings Graham when the year before, she was thrown off a trolley for being black. He won the case, which led to desegregation of NYC's trolley lines.