Citizens in St. Louis had grown used to seeing the grim-faced, rumpled man roaming the streets, looking for work. After abruptly quitting the Army, he had failed at farming and rent-collecting and had lost out on a chance to be county engineer. He was broke. And very nearly broken.

Still, he clung to the fortune he had received from a soothsayer. “Something will happen very soon and then I will begin to rise in the world,” he told his wife.

What happened was the Civil War. And only 10 years after selling firewood from a cart to make ends meet, Ulysses Simpson Grant stood at the Capitol, symbol of the nation he was credited with saving, and was sworn in as president of the United States.

That improbable rise is at the heart of Ron Chernow’s masterful and often poignant biography, a 1,000-page brick of a book that nevertheless moves quickly — much like its subject in war — and persuasively upends the conventional take on Gen. Grant as a butcher on the battlefield and President Grant as a bumbler in the White House.

Chernow presents Grant as one of the great military strategists in history, outdoing his more storied Confederate foes with his brains as much as his troops, and as a civil rights president who ushered freed blacks into the mainstream of American society before Southern hostility and Northern apathy unraveled the gains made during Reconstruction.

Grant has, in fact, gotten consistently high marks in recent years from a string of historians seeking to revise William McFeely’s generally negative portrayal of the general-cum-president in his 1981 Pulitzer Prize-winning book.

But Chernow’s take has special cachet, one that might well succeed in cementing Grant’s historical fortunes for generations. Not only is Chernow widely considered one of the best nonfiction writers at work today, but his acclaimed “Alexander Hamilton” was the inspiration for Lin-Manuel Miranda’s hot musical, marking him as the rare biographer who is well-known to the general public.

Grant’s story might be tougher to put to music. While Hamilton was famously colorful, Grant was Sphinx-like, modest in his Methodist way, not given to big gestures and often hard for even close associates to fathom. Short, slight and painfully reserved, he was easy to overlook and often was.

In 1861, a penniless Grant was clerking in his father’s leather-goods shop when the South seceded. The West Point graduate and Mexican War veteran volunteered his services and was placed in charge of an Illinois volunteer regiment. His star began to soar.

After crowning his success in the west at Vicksburg and Chattanooga, Grant was made lieutenant general (the first since George Washington) and brought east by Lincoln to take on Robert E. Lee. He handled Lee’s surrender at Appomattox with uncommon wisdom and charity, winning the grudging respect of Southerners and beginning the uneven process of healing the nation.

The Civil War years comprise the best part of Chernow’s book, a familiar tale that nonetheless becomes gripping in his telling. The war unleashed qualities in Grant that must have been there all along, Chernow writes: a gift for winning his soldiers’ respect, a shrewd sense for knowing when and where to strike, a knack for reading opposing generals and a fearlessness unmoved by daunting odds.

Grant was a natural choice for president in 1868 and won handily. But his lack of political experience and his native inclination to trust people made him incapable of heading off a series of scandals and fraudulent behavior among underlings that, while not directly involving him, badly tarnished his reputation.

Was Grant an alcoholic? Chernow says yes and documents various drunken episodes, some of them surely exaggerated and most occurring when he was lonely for home or bored for long stretches. He largely avoided imbibing during the war, despite the rumors that followed him everywhere.

Chernow holds Grant accountable for his missteps in the White House, but argues they have unjustly overshadowed his real legacy as president: shutting down the Ku Klux Klan and protecting the civil liberties of African-Americans with troops and vigorous federal prosecution. Succeeding presidents, Chernow writes, obscured much of the progress Grant had made by undoing many of those hard-won gains.

Grant waged his final battle against his own mortality, racing to finish his memoirs while dying of throat cancer. The result, finished a week before he died in 1885, is thought to be the best book ever written by a U.S. president. Royalties came to more than $400,000, money that his widow badly needed; in a final blow, he had lost their life savings to a corrupt investment partner.

Ulysses Grant, who once thought he might like to teach college math, didn’t plan most of what happened to him. But rarely has a consequential American life played out in such dramatic fashion. Chernow’s gracefully written biography, which promises to be the definitive work on Grant for years to come, is fully equal to the man’s remarkable story.

Kevin Duchschere is a Star Tribune editor • 612-673-4455

By: Ron Chernow.
Publisher: Penguin Press, 1,074 pages, $40.
Event: Talking Volumes, 7 p.m. Oct. 31, Fitzgerald Theater, 10 E. Exchange St., St. Paul. Tickets $23-50.