once admitted as States they have thenceforward the full rights of the
original States. Within all the Territories, while they remained under
its jurisdiction it lay with Congress to determine whether slavery should
be lawful or not, and, when any portion of them was ripe for admission to
the Union as a State, Congress could insist that the new State's
Constitution should or should not prohibit slavery. When the
Constitution of the Union was being settled, slavery was the subject of
most careful compromise; but in any union formed between slave States and
free, a bitter root of controversy must have remained, and the opening
through which controversy actually returned was provided by the
Territories.

On all other matters the makers of the Constitution had in the highest
temper of statesmanship found a way round seemingly insuperable
difficulties. The whole attitude of "the fathers" towards slavery is a
question of some consequence to a biographer of Lincoln, and we shall
return to it in a little while.


2. _Territorial Expansion_.

A machine of government had been created, and we are shortly to consider
how it was got to work. But the large dominion to be governed had to be
settled, and its area was about to undergo an enormous expansion. It
will be convenient at this point to mark the stages of this development.

The thirteen Colonies had, when they first revolted, definite western
boundaries, the westernmost of them reaching back from the sea-board to a
frontier in the Alleghany Mountains. But at the close of the war Great
Britain ceded to the United States the whole of the inland country up to