Isaiah Thornton Montgomery (May 21, 1847 – March 5, 1924) was the founder of Mound Bayou, Mississippi, an all-black community.

The Montgomery children learned to read and write due to their father's influential position on the Davis Bend plantation.

His father had long dreamed of establishing an independent black colony; by the time of his death, the Reconstruction era had ended and African Americans struggled to maintain themselves against white supremacists.

With his cousin Benjamin T. Green, he bought property in the northwest frontier of Mississippi Delta bottomlands to found Mound Bayou in 1887.

[6] With little ability to challenge it, Montgomery accepted the clause, arguing that while it was "apparently one of unfriendliness" to blacks it was in the public interest to prevent illiterates from voting.

He also lamented having heard in Montgomery "a groan of bitter anguish born of oppression and despair" and a voice of a "soul from which all hope had vanished.