Article 4, Section 3, Clause 1
James Madison, Federalist, no. 43, 290--9123 Jan. 1788
In the articles of confederation no provision is found on this important subject. Canada was to be admitted of right on her joining in the measures of the United States; and the other colonies, by which were evidently meant, the other British colonies, at the discretion of nine States. The eventual establishment of new States, seems to have been overlooked by the compilers of that instrument. We have seen the inconvenience of this omission, and the assumption of power into which Congress have been led by it. With great propriety therefore has the new system supplied the defect. The general precaution that no new States shall be formed without the concurrence of the federal authority and that of the States concerned, is consonant to the principles which ought to govern such transactions. The particular precaution against the erection of new States, by the partition of a State without its consent, quiets the jealousy of the larger States; as that of the smaller is quieted by a like precaution against a junction of States without their consent.
The Founders' Constitution
Volume 4, Article 4, Section 3, Clause 1, Document 7
The University of Chicago Press
Hamilton, Alexander; Madison, James; and Jay, John. The Federalist. Edited by Jacob E. Cooke. Middletown,
Easy to print version.