The Human Division is a science fiction novel by American writer John Scalzi, the fifth book set in the Old Man's War universe.

[1] Following the events of The Last Colony, John Scalzi tells the story of the fight to maintain the unity of the human race.

For generations the CU had defended humanity against hostile aliens, deliberately keeping Earth an ignorant backwater and a source of military recruits.

[2] As the story progresses, it deals with how humanity fares in a universe filled with other sentient races and without a growing military force to clash with them.

The book was published at e-book retailers between 15 January and 9 April 2013 as digital serials with thirteen episodes.