Let us now go back to the period immediately following the adoption of the Constitution, and trace the birth of new States. The first State admitted was Vermont. The territory which now forms Vermont was claimed by New Hampshire, which granted the land to settlers. For this reason it was called "The New Hampshire Grants." New York claimed it also, and tried to make the people buy their lands over again. But the "Green Mountain Boys" kept up an independent government of their own throughout the Revolution. In 1791 the State was admitted under the name of Vermont, a word of French derivation meaning "Green Mountain."

Kentucky was a part of Virginia, and was settled by Virginians, who took with them their slaves, their agricultural habits, and their military spirit. With the consent of Virginia, Kentucky was separated from that State and admitted to the Union in 1792. The people of this country have generally emigrated in pretty straight lines to the westward. As Virginians broke over the mountains into Kentucky, so North Carolinians crossed into the valleys of Tennessee. North Carolina gave up her right to the territory west of the mountains soon after the Constitution was formed, and what is now Tennessee was part of the Southwestern Territory, until it was admitted to the Union in 1796.

These two States, Kentucky and Tennessee, had slaves. But the Ordinance of 1787, did not allow slaveholding in the territory north of the Ohio River; so that all the States formed out of that territory were free states from the beginning. In the two years following the passage of this ordinance, twenty thousand people made their way down the Ohio River. But the American Indian wars checked the settlement of the country until after General "Mad" Anthony Wayne defeated the American Indians on the Maumee River in Ohio. Ohio was admitted to the Union February 19, 1803.

It was more than nine years before another State was admitted. In 1812 the southern part of the great territory bought from France was admitted, under the name of Louisiana—the name at first given to the whole. Thus, when the War of 1812 began, the old Union of thirteen States had increased to eighteen.

The second war with England, and particularly the naval battles and the crushing defeat which General Andrew Jackson inflicted on the British troops at New Orleans, made the United States respected in Europe as it had never been before. Emigrants began to flock to America. The peace with the American Indians caused the Mississippi Valley, then called "The Far West," to fill up rapidly. In more than thirty years after the Revolution, only five States were added to the Union; but the next six States were admitted in six successive years—Indiana, next west of Ohio, in 1 8 16. The defeat of the Creeks had opened the Southwest; and the new State of Mississippi, between Tennessee and Louisiana, was admitted in 1817. Illinois, west of Indiana, was admitted in 1818; and Alabama filled the gap between Mississippi and Georgia in 1819. In 1820 the District of Maine, long attached to Massachusetts, though separated from it geographically, was admitted as an independent State.

By 1820, therefore, all the territory east of the Mississippi except the extreme northern portion, now included in Michigan and Wisconsin, had been made into States, and the State of Louisiana had been made out of the territory which had been bought from France. But, by this time, a new State on the west of the Mississippi River was knocking at the door of the Union. This was Missouri. Over the admission of this state there was a great debate, lasting through three sessions of Congress.

The cause of this debate was the fact that Missouri proposed to come in as a slave State. The bringing of slaves into the United States had been forbidden in 1808. The States north of the southern line of Pennsylvania had all, before 1820, taken measures to free their slaves. The States south of the southern line of Pennsylvania, having- much of their wealth in slaves, and cultivating crops that seemed to require their labor, had by this time mostly given up the thought of freeing their slaves. So that there were now two classes of States in the Union: free states and States having slaves. Each of these divisions of the Union was afraid that the other would get control of the country. It had usually been the custom, in admitting new States, to bring in one from the North and one from the South, to keep the balance good.

But Missouri brought up a new question. According to the Ordinance, in 1787, the States north of the Ohio had all come in as free states; but those to the south of that river had been allowed to enter as slaveholding States. Louisiana had been purchased as slaveholding territory, and was admitted as a slave State. But now the question arose whether all the great region bought from France was to be added to the Southern side of the scale. Missouri was west of the Mississippi, and so far north as to seem to break into the line of free states.

Most of the people at the North wished all the new territory made into free states; most of the people at the South wished to have it all open to settlement by Southern people with slaves. The question was finally decided by letting Missouri come in as a slave State, but slavery was at the same time forever forbidden in the rest of the territory north of the southern line of Missouri. Thus all the territory to the north and west of that State would be free. This was known as the Missouri Compromise. It was adopted in 1820, and Missouri was finally admitted in 1821. Henry Clay, the most famous of the orators and political leaders of the day, was very active in promoting this measure.

The "Old Thirteen" had now grown to twenty-four. The expansion of the nation in population and wealth was very rapid. In 1820 there were more than nine and a half million people in America. This was about three times as many as there were when the Revolutionary War was ended.