Perhaps the laziest thing a reviewer can ask is, "Why another book on this subject?" The question often answers itself. Certain topics occupy iconic places in our historical imagination, giving rise to endless fascination. Better to ask, "What is important to the writer? What matters so much that he or she must enter a crowded field to provide it?"

The good news about Nathaniel Philbrick's "The Last Stand: Custer, Sitting Bull, and the Battle of the Little Bighorn" is that his priority is to tell a good story well. For those who have forgotten everything about U.S. history, this is a national epic. On June 25, 1876, Lt. Col. George Armstrong Custer -- a hero in the Civil War and a controversial figure afterward -- led the 7th Cavalry Regiment against thousands of Lakota and Northern Cheyenne, who were galvanized by Sitting Bull. Custer and nearly 270 of his men perished.

Philbrick, winner of the National Book Award for "In the Heart of the Sea" and a Pulitzer finalist for "Mayflower," focuses tightly on the campaign and battle. Readers who hope for fast-paced action and complicated characters will not be disappointed. That is a true accomplishment, considering the conflicting sources and bitter debate clouding these events. Inevitably some will dispute his version, yet he displays sound judgment throughout.

Readers wishing for more, though, may be less satisfied. To the extent that Philbrick wishes to add to our knowledge, he limits himself to details. He stresses his personal inspection of the battlefield and discovery of Pvt. Peter Thompson's unpublished account. But the net increase seems trivial, except to buffs who obsess over every minor point.

When Philbrick rises above the level of who-rode-where, he sometimes stumbles. For example, he writes that "the press had erupted in outrage" over President Ulysses S. Grant's treatment of Custer. In fact, newspapers at the time were explicitly partisan, indeed central to the party system; the criticism, then, was political, not the considered judgment of neutral journalists.

Nor does he say anything particularly original about the battle's significance. His interpretive edge is sharpest with the small scale, which may explain the structural confusion of his concluding chapters. He jumps between the death of Sitting Bull in 1890 and the 1876 journey of the steamboat Far West, bearing news of Custer's annihilation -- a device that comes across as an attempt to inject drama and pathos into the anticlimactic aftermath. Put simply, the victorious American Indians dispersed and were hounded onto reservations, leading to misery, murder and the tragedy of Wounded Knee.

I finished this book feeling that something more profound can still be said about so iconic an event. But that is not what concerns Philbrick. Nor will it matter to many readers, who will be rewarded with a gripping tale, matched with numerous excellent maps and fine illustrations, many in full color.

T.J. Stiles is the author of "The First Tycoon: The Epic Life of Cornelius Vanderbilt," winner of the National Book Award and the Pulitzer Prize for nonfiction, now available in paperback.