In the summer of 1862, President Lincoln called General Henry W. Halleck to Washington, D.C., to take command of all Union armies in the death struggle against the Confederacy. For the next two turbulent years, Halleck was Lincoln's chief war advisor, the man the President deferred to in all military matters. Yet, despite the fact that he was commanding general far longer than his successor, Ulysses S. Grant, he is remembered only as a failed man, ignored by posterity.

In the first comprehensive biography of Halleck, the prize-winning historian John F. Marszalek recreates the life of a man of enormous achievement who bungled his most important mission. When Lincoln summoned him to the nation's capital, Halleck boasted outstanding qualifications as a military theorist, a legal scholar, a brave soldier, and a California entrepreneur. Yet in the thick of battle, he couldn't make essential decisions. Unable to produce victory for the Union forces, he saw his power become subsumed by Grant's emergent leadership, a loss that paved the way for Halleck's path to obscurity.

Harnessing previously unused research, as well as the insights of modern medicine and psychology, Marszalek unearths the seeds of Halleck's fatal wartime indecisiveness in personality traits and health problems. In this brilliant dissection of a rich and disappointed life, we gain new understanding of how the key decisions of the Civil War were taken, as well as insight into the making of effective military leadership.

"Civil War biographies do not come much better, if at all, than John F. Marszalek's account of Henry Wager Halleck. Written with scholarly precision and aplomb, it recounts the life and contributions of the Union's top soldier, 1862–1864, from his childhood on a New York farm...Researched in depth, closely reasoned, and energetically presented, Marszalek's biography will long remain the standard account of Lincoln's commander in chief." - Journal of American History

"John Marszalek has provided the most detailed and authoritative account of Halleck's early life, initial military career and later professional success as a lawyer...The book, as one would suspect from such an author, is skillfully put together and agreeably written." - Journal of Military History

"With this work, John F. Marszalek fills a large gap in the nineteenth-century U.S. historical record. Despite the considerable roles played by Henry Wager Halleck in disparate fields, no other full biography of the man exists...In preparing this life of Halleck, Marszalek certainly did his homework...Adding to the authoritative nature of the volume is its extensive scholarly apparatus, with forty-six pages of endnotes, plus twenty-seven well-chosen illustrations spanning Halleck's life...Marszalek's searching and balanced study offers frequent surprises for even the most attentive students of the era." - American Historical Review

"The reader is presented with a richly detailed and engrossing story of one of America's most notable and influential soldiers of the nineteenth century. John Marszalek is to be commended for his efforts on completing this biography, and he has made a valuable contribution to the study of soldiers and the profession of arms. This book is recommended to those interested both in the US Civil War and army leadership studies." - Canadian Army Journal

"John F. Marszalek has provided a most welcome addition to the literature of the Civil War and American history with his biography of Henry Wager Halleck, an outstanding and influential figure in the Old Army, a founding father of California, a legal authority, a highly successful businessman and architect, and an author of incredible breadth...One must notice Marszalek's bibliographical essay. It is excellent and should stand as a model. For that matter, the author's objectivity shines throughout. He respects his subject and feels an obligation to the individual and to history...To the joy of the reader, Marszalek writes clearly and unpretentiously. He uses humor and irony effectively and has an eye for humor in a man regarded as grim beyond belief, carefully demonstrating that Halleck had a sharp wit and a sense of humor." - Journal of Southern History

"Painstakingly researched, well written and judicious in its approach, this volume offers the reader valuable insights into the foundation years of the state of California and penetrative analysis of the unstable nature of the command structure of the Union during the war, as well as providing us with what will surely be the standard biography of Halleck for many years to come." - Journal of American Studies