the northwest was reserved for the formation of free States.
Arkansas became a slave State in 1836 and Michigan was admitted
as a free State in the following year.

With the admission of Arkansas and Michigan, thirteen slave
States were balanced by a like number of free States. The South
still had Florida, which would in time become a slave State.
Against this single Territory there was an immense region to the
northwest, equal in area to all the slave States combined, which,
according to the Ordinance of 1787 and the Missouri Compromise,
had been consecrated to freedom. Foreseeing this condition, a few
Southern planters began a movement for the extension of territory
to the south and west immediately after the adoption of the
Missouri Compromise. When Arkansas was admitted in 1836, there
was a prospect of the immediate annexation of Texas as a slave
State. This did not take place until nine years later, but the
propaganda, the object of which was the extension of slave
territory, could not be maintained by those Who contended that
slavery was a curse to the country. Virginia, therefore, and
other border slave States, as they became committed to the policy
of expansion, ceased to tolerate official public utterances
against slavery.

Three more or less clearly defined sections appear in the later
development of the crusade. These are the New England States, the
Middle States, and the States south of North Carolina and
Tennessee. In New England, few negroes were ever held as slaves,
and the institution disappeared during the first years of the
Republic. The inhabitants had little experience arising from
actual contact with slavery. When slavery disappeared from New