The North, after several slave States, which were at first doubtful, had adhered to it, had more than double the population of the South; of the Southern population a very large part were slaves, who, though industrially useful, could not be enlisted. In material resources the superiority of the North was no less marked, and its material wealth grew during the war to a greater extent than had perhaps ever happened to any other belligerent power. These advantages were likely to be decisive in the end, if the North could and would endure to the end. But at the very beginning these advantages simply did not tell at all, for the immediately available military force of the North was insignificant, and that of the South clearly superior to it; and even when they began to tell, it was bound to be very long before their full weight could be brought to bear. And the object which was to be obtained was supremely difficult of attainment. It was not a defeat of the South which might result in the alteration of a frontier, the cession of some Colonies, the payment of an indemnity, and such like matters; it was a conquest of the South so complete that the Union could be restored on a firmer basis than before. Any less result than this would be failure in the war. And the country, to be thus completely conquered by an unmilitary people of nineteen millions, was of enormous extent: leaving out of account the huge outlying State of Texas, which is larger than Germany, the remaining Southern States which joined in the Confederacy have an area somewhat larger than that of Germany, Austria-Hungary, Holland, and Belgium put together; and this great region had no industrial centres or other points of such great strategic importance that by the occupation of them the remaining area could be dominated. The feat which the Northern people eventually achieved has been said by the English historians of the war (perhaps with some exaggeration) to have been "a greater one than that which Napoleon attempted to his own undoing when he invaded Russia in 1812."