Arna Bontempts, the author of Black Thunder, says in the introduction to the 1968 edition of the book,
"Time is not a river. Time is a pendulum."
With these words, he is stating the main theme of his work - history repeats itself, and issues that were important during one span of time will become pertinent again. Bontempts wrote Black Thunder in the mid-1930s, and looks back upon the slave risings of the past as "harbingers" of unrest to come. Although he could not have known about the fight for civil rights for African Americans that would take place in the 1960s, thirty years in the future, he felt sure that a rebellion of some sort was coming in relation to this issue. The struggle for justice was not yet finished, and Bontempts believed that, like a pendulum, the movement for civil rights for all would come to the forefront of history once again in the future.