Americans have long had a fascination with the exploration of the West. Ever since Thomas Jefferson's obsession with the natural world, in which he realized the scientific value and political gain for this country's westward expansion, politicians, military leaders and average pioneer citizens have all played important roles in reaching the Pacific shore.

Robert Morgan, known for his well received novel "Gap Creek" and his popular biography of Daniel Boone, has now written a fine portrait of 10 pivotal individuals who shaped this expansion. His hope was that "recounting them briefly and in sequence here may create an integrated narrative where the separate lives link up and illuminate each other."

Beginning with Jefferson and ending with John Quincy Adams -- from the origins of moving westward to California's Gold Rush -- Morgan offers mini-biographies of politicians Jefferson, Adams, Andrew Jackson, James Polk and Sam Houston; diplomat Nicholas Trist; Gen. Winfield Scott; and explorers Kit Carson, David Crockett and John Chapman, better known as Johnny Appleseed.

Morgan's accounts of these key players make for an intriguing journey westward. While it seems today an inevitable consequence that the United States would stretch from coast to coast, there were many obstacles to this realization in the 19th century. European powers, the English, Spanish and French, all had land and economic interests at stake, as did our neighbors to the south in Mexico (one of Morgan's noble efforts in "Lions of the West" was to incorporate the work of Mexican historians -- often overlooked in American histories -- to bring in alternative viewpoints to the historical record). There was also the problem of native peoples who had inhabited all this land for centuries. And there were challenges of geography.

"Lions of the West" reveals many ties among these individuals and reminds us of their frailties (after Sam Houston was arrested for beating a congressman, he was Andrew Jackson's guest in the White House and was defended in court by Francis Scott Key). Most important, Morgan's book gives us a vivid sense of these 10 strong personalities; tells us how political meanderings and shenanigans created and distracted this country's development westward; and notes that the pressing issue of the century -- slavery -- was largely put aside during the exploration, with disastrous consequences a few decades later.

Despite its impressive coverage and integration of current historical assessment, "Lions of the West" lacks details of other important people and forces, particularly voices of the Indians and examples of attacks and atrocities against them. This is ultimately the story of the conquerors and their land grab, but that, sadly, is the big story of the westward expansion. Morgan has given us a stimulating and engaging account of how it all came about.

Jim Carmin, a member of the National Book Critics Circle, lives in Portland, Ore.