enforce the rights of certain heirs under a system of perpetual leases derived from the Dutch patroons. These disorders were not promptly suppressed, because popular sympathy was with their promoters; and the perpetual leases were at length displaced by tenures in fee-simple.1

There was an easy escape from these conditions, and it serves to explain the westward impulse. More freedom and better opportunity were always to be found “a little further on"; and the grand march of home-seekers swept over the Alleghanies and even the Rockies, ending only at the Pacific coast.

Immigration from Europe began to increase rapidly after 1830, and it was especially large during the years 1846-1848, which were marked by famine in Ireland and revolution on the Continent. From 1845 to 1850 the average annual influx was about three hundred thousand. The immigrants distributed themselves mainly in Massachusetts, New York, and Pennsylvania; but a large number, especially of Germans, were already entering the country north of the Ohio and the upper part of the Mississippi Valley.2

The total area of the United States in 1840 was about eighteen hundred thousand square miles, of which the settled part, with as many as two in

1 Cheyney, Anti-Rent Agitation in the State of New York (Univ. of Pa., Publications, No. 2).

"U. S. Seventh Census (1850), Population, xxxviii.

habitants to the square mile, was a little over eight hundred thousand. The frontier lay along the western border of Louisiana, Arkansas, and Missouri; excluded a narrow strip of northern Missouri, the upper third of the present area of Maine, and most of the peninsular part of Florida, and included the southeastern part of the territory of Iowa and the southern part of the territory of Wisconsin and of the state of Michigan.1

The total population in 1840 was 17,069,453, of whom 14,195,805 were white and 2,873,648 were negroes. The distribution was as follows: in the North Atlantic division, 6,618,758 whites and 142,324 negroes; in the South Atlantic, 2,327,982 whites and 1,597,317 negroes; in the North Central, exclusive of Missouri - which for the purposes of this enumeration should be grouped with the slaveholding states-2,938,307 whites and 29,533 negroes; and in the South Central, together with Missouri, 2,304,658 whites and 1,104,474 negroes." Of the negroes in the slave-holding states, about three hundred thousand were free, of whom about seventy-five thousand were in Maryland and fiftyfive thousand in Virginia.3

During the period 1790-1840 the centre of the entire population of the United States moved west

1 U. S. Twelfth Census (1900), Statistical Atlas, Plate 7. 'These figures are from U. S. Census Bureau, Negroes in the United States (Bulletin No. 8), 101-103.

'U. S. Seventh Census (1850), Population, xxxviii.

ward, keeping close to the parallel of 39°, from a point twenty-three miles east of Baltimore to a point sixteen miles south of Clarksburg in what is now West Virginia. Meanwhile the centre of negro population had moved southwestward from a point twenty-seven miles southeast of Petersburg, Virginia, to the neighborhood of Asheville, North Carolina. While the whites were pushing westward, the negroes were evidently moving towards the cotton and cane belt in the genial lowlands of the South.'

In 1840 only eight and a half per cent. of the total population lived in cities of eight thousand or more inhabitants. There were forty-four such cities, most of which, especially the more populous, were in the North Atlantic states. The slave-holding states contained thirteen. The states showing the largest concentration in cities, with approximate percentages, were Rhode Island, with 38; Louisiana, 30; Massachusetts, 27; Maryland, 22; New York, 20; Pennsylvania, 14; Delaware, 11. The cities having over one hundred thousand inhabitants, with their population in round numbers, were New York, 312,000; Philadelphia, 220,000; Baltimore, 102,000; and New Orleans, 102,000. St. Louis had only a little more than 16,000, and Chicago less than 5000. The difference between the

1 U. S. Twelfth Census (1900), Statistical Atlas, 37, and Plate 16; location estimated from data given in U. S. Census Bureau, Negroes in the United States (Bulletin No. 8), 24, 25.

2 U. S. Seventh Census (1850), Compendium, 193.

industrial organization in the manufacturing and commercial North and that in the agricultural South is well illustrated by the relative excess of urban population in the former.1

The most important modification of the expansion movement was that due to the progress of sectionalization. Up to 1830 the drift of American political development was, on the whole, strongly nationalistic, because of certain permanent tendencies which exist among all progressive peoples and work for economic and political centralization. Improved means of intercommunication, the growth of the West, and the persistent and successful struggle for a satisfactory international status for the American Union had more or less completely overcome the particularism that was so strong before the War of 1812. After 1830, however, the states gradually separated into two great groups, a northern and a southern, with antagonistic interests and ideals, whose differences grew ever more pronounced and intense until the end was civil war.'

The causes of sectionalization were fundamentally economic. They consisted in diverse natural conditions which tended irresistibly towards the production of two radically different industrial systems and two inharmonious varieties of civilization.

1 U. S. Twelfth Census (1900), Statistical Atlas, 40, and Plates

20, 22.

2 Cf. Chadwick, Causes of the Civil War (Am. Nation, XIX.), chap. iii.

The effect of these conditions was that, while the North changed rapidly, the South continued relatively the same. At first both had slavery; but the North found it unprofitable and gave it up, while the South, where the climate and other conditions invited the use of slave labor, held on to it, and finally came to look upon it as an economic necessity. Both alike in the earlier stages of their history depended for subsistence mainly on agriculture; and in the South the extent of fertile land and the availability of slaves for its cultivation emphasized this dependence, and in this way served to hinder diversification of industries and even of crops; while in the North attention was rapidly diverted towards commerce and manufactures. Both alike, when independence was declared, and even when the Constitution was adopted, regarded the Union as a confederacy from which any state might withdraw if it desired to do so, and this view the South continued to hold afterwards even to the extreme of secession and of civil war; but the North, seeing the advantage of the national machinery provided by the Constitution for the support of its policy and the promotion of its interests, was gradually led to use its growing strength through that machinery and thus to adopt the nationalistic attitude. Under such circumstances it was but natural for the weaker South, even if there had been far less historical justification for its attitude, to fall back on the defen