stem of indenture of the colored servant; and
the effort of Southern settlers in Indiana and in Illinois to
reintroduce slavery are indicative of the importance of the pro-slavery
element in the Northwest. But the most significant early manifestation
of the rival currents of migration with respect to slavery is seen in
the contest which culminated in the Missouri Compromise. The historical
obstacle of the Ordinance, as well as natural conditions, gave an
advantage to the anti-slavery settlers northwest of the Ohio; but when
the Mississippi was crossed, and the rival streams of settlement mingled
in the area of the Louisiana Purchase, the struggle followed. It was an
Illinois man, with constituents in both currents of settlement, who
introduced the Missouri Compromise, which made a _modus vivendi_ for the
Middle West, until the Compromise of 1850 gave to Senator Douglas of
Illinois, in 1854, the opportunity to reopen the issue by his
Kansas-Nebraska bill. In his doctrine of "squatter-sovereignty," or the
right of the territories to determine the question of slavery within
their bounds, Douglas utilized a favorite Western political idea, one
which Cass of Michigan had promulgated before. Douglas set the love of
the Middle West for local self-government against its preponderant
antipathy to the spread of slavery. At the same time he brought to the
support of the doctrine the Democratic party, which ever since the days
of Andrew Jackson had voiced the love of the frontier for individualism
and for popular power. In his "Young America" doctrines Douglas had also
made himself the spokesman of Western expansive tendencies. He thus
found important sources of popular support when he invoked the localism
of his section. Western appeals to Congress for aid in internal
improvements, protective tariffs, and land grants had been indications
of nationalism. The doctrine of squatter-sovereignty itself catered to
the love of national union by presenting the appearance of a
non-sectional compromise, which should allow the new areas of the Middle
West to determine their own institutions. But the Free Soil party,
strongest in the regions occupied by the New York-New England colonists,
and having for its program national prohibition of the spread of slavery
into the territories, had already found in the Middle West an important
center of power. The strength of the movement far surpassed the actual
voting power of the Free Soil party, for it c