No apology is offered for presenting to the public the only authentic account of Brigham Young, of his polygamous family, and of that complicated and incongruous system of social and political machinery, called Mormonism. The only form of religion in this country which refuses to conform either to the spirit of progress and improvement and enlightened humanity which characterizes the age in which we live, or to our laws and the genius of our free institutions,—drawing constantly from foreign countries hosts of votaries, impelled hither not by a love of republicanism, but rather by a desire to exchange a political for a religious monarchy,—is Mormonism, which presents an antagonism to our Government, and can scarcely fail to result in national trouble. The elements of a second rebellion are in active progress in Utah, and, as in the case of the slavery rebellion, the great danger lies in failing to place a proper estimate upon the power of those elements for mischief, and to take the proper precautions in time. Religious fanaticism is more active, and, when hostile, more dangerous, than political ambition; hence the arrogant and intolerant spirit, and the bitter hostility of the Mormons, are more worthy the serious attention of our statesmen than would be the opposition of so many mere political traitors. Again; their power for mischief is much increased by the position they occupy upon the great thoroughfare between the eastern and western portions of our country. It is with the view of calling the attention of the Government and of the people of the country to the dangerous character of this monarchy growing up in the midst of the Republic, that the political history of Utah has been written. The chief interest of the work, however, with a large class of readers, will doubtless consist in the information it contains, relative to the family and social relations of the celebrated Mormon leader. These, and all other facts contained in this volume, may be relied upon as true, and many of them are now published for the first time.