"May has produced his magnum opus. . . . Unquestionably the finest volume yet written on the subject of filibustering."
Civil War History
"This is one of those rare books that [combines] an interesting topic and excellent writing.
"[This book] uncovers issues largely ignored by previous scholars and connects filibusterism with the war with Mexico and the Civil War.
(Hispanic American Historical Review
"Manifest Destiny's Underworld
is a well-researched and thoughtful analysis of a neglected yet important topic of American history.
(North Carolina Historical Review
From the Inside Flap
In the first full history of 19th-century American filibusters, illegal invasions of foreign countries with whom the US was formally at peace, May explores what drew thousands of men to join these mercenary expeditions and considers the relationship between filibustering and broader issues of American imperialism.