The principal characters are: The uneducated, slow-witted Bartly Madden; Kinsella, the disciplined commander of a small band of insurgents; Stapleton, an anarchist and would-be poet; and Tommy Colgan, a youth consumed by fear and self-doubt.

[2][3] Insurrection received generally positive reviews, although it was compared unfavourably to some of O'Flaherty's other work, such as The Informer and Famine.

"[4] Writing in The Saturday Review, a U.S. literary magazine, Thomas Sugrue said, "Like the rebellion itself, the book is brief, sharp, blazing with action and lit by a radiance of idealism which softens the ugly reality with which it deals, while at the same time illuminating the ugliest of its details.

"[3] The Irish monthly literary publication The Bell (1940–54) was more reserved: its (anonymous) reviewer said, "It might be said that only readers who know nothing of about Easter Week could get the best value out of Insurrection.

"In trying to make fiction out of what amounts to a theory of revolutionary history," Hildebidle wrote, "he [O'Flaherty] produces characters with none of the persuasive energy and substance of his earlier novels".