ict, spy, detective, congressional candidate, adventurer, and con artist spanned the Civil War, Reconstruction, and Gilded Age. His life touched many of the most prominent figures of the era, including Abraham Lincoln, Jefferson Davis, and Ulysses S. Grant. One contemporary newspaper reported that Cowlam "has as many aliases as there are letters in the alphabet." He was a chameleon in a world of strangers, and scholars have overlooked him due to his elusive nature. His intrigues reveal how Americans built trust amid the transience and anonymity of the nineteenth century. The stories Cowlam told allowed him to blend in to new surroundings, where he quickly cultivated the connections needed to extract patronage from influential members of American society.

Whereas historians of capitalism have uncovered the vulnerabilities of an economic system dependent upon trust and personal relationships, Cowlam's life exposes the liabilities of a political system constructed on the same foundations. Rather than perpetrating frauds against average citizens, Cowlam reserved his most fantastic schemes for officials in the highest levels of government. He is the only person to receive presidential pardons from both Abraham Lincoln and Jefferson Davis during the Civil War. When the fighting ended, he conned his way into serving as a detective investigating Lincoln's assassination, later parlaying that experience into positions with the Internal Revenue Service and the British government.

Reconstruction offered additional opportunities for Cowlam to repackage his identity. He convinced Ulysses S. Grant to appoint him U.S. marshal and persuaded Republicans in Florida to allow him to run for Congress. After losing the election, Cowlam moved to New York, where he became a serial bigamist and started a fake secret society inspired by the burgeoning Granger movement. When the newspapers exposed his lies, he disappeared and spent the next decade living under an assumed name. He resurfaced in Dayton, Ohio, claiming to be a Union colonel suffering from dementia in an effort to gain admittance into the National Soldiers' Home. In A Wonderful Career in Crime, Frank W. Garmon Jr. brings Cowlam's stunning machinations to light for the first time.