National Hall is a former venue in Philadelphia, Pennsylvania, located at 1222–24 Market Street, between Twelfth and Thirteenth Streets. It was one of the most popular venues in the city, site of concerts, lectures, meetings, and political speeches. It opened on January 8, 1856, with a "grand operatic concert". While it existed, from 1856 to 1873, it was the main venue in Philadelphia for speakers for abolitionism and other progressive causes.

Octavius Valentine Catto was an American educator, intellectual, and civil rights activist. He became principal of male students at the Institute for Colored Youth, where he had also been educated. Born free in Charleston, South Carolina, in a prominent mixed-race family, he moved north as a boy with his family. After completing his education, he went into teaching, and becoming active in civil rights. He also became known as a top cricket and baseball player in 19th-century Philadelphia, Pennsylvania. A Republican, he was shot and killed in election-day violence in Philadelphia, where ethnic Irish of the Democratic Party, who were anti-Reconstruction and had opposed black suffrage, attacked black men to prevent their voting.