Shawcross deftly reexamines the tragicomic rule of the Austrian archduke Ferdinand Maximilian, the Habsburg prince whom France briefly imposed on Mexico in the 1860s. Maximilian is often portrayed as a vainglorious buffoon, a quixotic old-school European aristocrat egged on by an ambitious wife. In Shawcross’s persuasive retelling, Maximilian was a well-intentioned, if flawed, Enlightenment ruler buffeted by the great forces of the mid-nineteenth century. Napoleon III, the French emperor, installed Maximilian in Mexico to challenge the growing power of the United States. Ultraconservative Mexican exiles championed him as an autocratic ruler to combat rising republican liberalism. Maximilian tried but failed to reconcile these opposing forces. After the end of the American Civil War, the United States reasserted the Monroe Doctrine, which sought to prevent further European colonization in the Western Hemisphere, and demanded that the French government withdraw from Mexico. Washington backed the uncompromising secular reformer Benito Juárez, who swept aside Maximilian’s forces and ordered the archduke’s execution by firing squad. In The Execution of Maximilian, the French painter Édouard Manet captured the proud stoicism of the defeated, abandoned Habsburg prince. Equally tragic was the fate of his young, brilliant wife, Carlota, who, after futilely pleading with the French emperor and Pope Pius IX for renewed support for her husband’s beleaguered kingdom, lost her sanity.