Admission of New States

New States may be admitted by the Congress into this Union; but no new States shall be formed or erected within the Jurisdiction of any other State; nor any State be formed by the Junction of two or more States, or Parts of States, without the Consent of the Legislatures of the States concerned as well as of Congress.

These words of the first clause of Section 3 of Article IV of the US Constitution give little sense of the power of the admissions clause. The US Congress subsequently added thirty-seven states into the Union, beginning with Vermont in 1791, Kentucky in 1792, and Tennessee in 1796.

The United States grew from sixteen states in 1800 to twenty-three states in 1820, twenty-six states in 1840, thirty-three states in 1860, thirty-eight states in 1880, forty-five states in 1900, and forty-eight states in 1920. Alaska and Hawaii were then admitted in 1959, even though they had been the possessions of the United States since 1867 and 1898, respectively; Puerto Rico may yet become a state. With the admission of these new states, the United States transformed from a federation consisting of a handful of states bordering the Atlantic Ocean and locked in continentally by Britain, France, and Spain to a continental republic that extended into the Arctic and almost halfway across the Pacific.


What the admissions clause does not make clear is that the ground for the admission of new states had been laid during the Constitutional Convention when the Confederation Congress passed the Northwest Ordinance under the Articles of Confederation on July 9, 1787. The Northwest Ordinance established a blueprint for the admission of new states formed from the land area owned by the US government. Nathan Dane ( 1752–1835 ), Thomas Jefferson, and James Monroe created a threepart process in the ordinance so that new lands settled by Americans could be annexed as US territories by Congress and then admitted as states. Congress was to administer the new land areas as “unorganized territories” “for the purpose of temporary government” (Sec. 1); once the territory had five thousand free male inhabitants it could then form its own government (Sec. 8, Sec. 11). Once the territory had sixty thousand free inhabitants it could then petition Congress for statehood, subject to the condition that the territory established a republican form of government (Art. 5). But Congress could admit states with fewer than sixty thousand residents (Art. 5) and “at as early periods as may be consistent with general interest” (Sec. 13).

In consequence, the United States’ admission of new states was achieved according to the principles of federal government, and the many new states subsequently added to the Union were able to join on an “equal footing” with the existing states. The delegates in Philadelphia did not explicitly include the equal-footing doctrine in the Constitution, and a 9–2 majority of the Committee of Detail voted to strike out proposed text, “If the admission [of new states] be consented to, the new States shall be admitted on the same terms with the original States.” The Founders did not want to limit congressional authority, and they were wary of the influence of new western states in the government. The equalfooting doctrine nonetheless remained at the core of the American system of government and undergirded the geographical expansion of the United States.


The text of the Tenth Amendment, adopted in 1791, further suggests the equal footing of the states with its terse declaration that “powers not delegated to the United States, nor prohibited by it to the States, are reserved to the States, respectively, or to the people.” Each of the enabling acts passed by Congress that admitted new states into the Union also specified that the new states be admitted “on an equal footing” with the original states.

The Supreme Court articulated the equal-footing doctrine in its 1845 decision in Pollard's Lessee v. Hagan, 44 U.S. 3 How. 212 212 ( 1845 ), in which the Court ruled that Alabama had the same ownership rights—in this case, those of the shores of its inland navigable waters and the submerged land underneath—as had the state of Georgia, which had formerly governed Alabama. “Alabama is … entitled to the sovereignty and jurisdiction over all the territory within her limits, subject to the common law, to the same extent Georgia possessed it, before she ceded it to the United States,” the Court ruled. “To maintain any other doctrine is to deny that Alabama has been admitted into the union on an equal footing with the original states” (44 U.S. at 222).

The US Supreme Court majority reaffirmed the equal-footing doctrine in Coyle v. Smith, 221 U.S. 559 ( 1911 ): “When a new State is admitted into the Union, it is so admitted with all of the powers of sovereignty and jurisdiction which pertains to the original states, and that such powers may not be constitutionally diminished, impaired or shorn away” (221 U.S. at 572). According to the Court's ruling in Coyle, “‘This Union’ was and is a union of States, equal in power, dignity, and authority, each competent to exert that residuum of sovereignty not delegated to the United States by the Constitution itself” (221 U.S. at 567).

Senator Henry Jackson of Washington State (3rd from right), Hawaii territorial governor William F. Quinn (2nd from right), and others celebrate Hawaiian statehood, March 1, 1959.

Senator Henry Jackson of Washington State (3rd from right), Hawaii territorial governor William F. Quinn (2nd from right), and others celebrate Hawaiian statehood, March 1, 1959.

As established in Spooner v. McConnell ( 22 F. 939 [1838] ), Scott v. Jones ( 46 U.S. 343 [1847] ), Case v. Toftus ( 39 F. 730 [1889] ), and other decisions, new states were to be admitted as equals to the original states with respect to their standing in legislative, executive, and judicial branches, and to their prerogatives as states of the Union. It did not preclude Congress's imposition of conditions on the admission of states or the preemption of state laws by congressional statutes. Equal footing did not mean equality of rights of the soil, per the terms of the Northwest Ordinance (Art. 4), and the Northwest Ordinance (and subsequent legislation admitting new states) reserved to the federal government the disposal of the soil of the territories, per the Supreme Court's ruling in Case v. Toftus; “equal footing” did not “require that the new state shall be admitted to any right in the soil thereof considered as property” (39 f. at 6).

Yet once admitted to the Union, states cannot secede, the US Supreme Court held in Texas v. White, 74 U.S. 700 ( 1869 )—ratifying President Abraham Lincoln's interpretation of the Union and US Constitution.


Congress can use its authority to delay the admission of new states. It matched a free state, Illinois ( 1818 ), with a slave state, Alabama ( 1819 ). With the Missouri Compromise of 1820, Congress restricted slavery in states north of 36°30’ (although exempting Missouri and Arkansas) and proceeded to admit new states in pairs, Maine ( 1820 ) and Missouri ( 1821 ), Arkansas ( 1836 ) and Michigan ( 1837 ), and Florida ( 1845 ) and Iowa ( 1846 ). The Kansas-Nebraska Act, which established “popular sovereignty” such that the white male electorate in the territories could themselves decide whether or not to allow slavery, effectively repealed the Missouri Compromise. The Supreme Court's decision in Dred Scott v. Sandford, 60 U.S. 393 ( 1856 ), did so formally.

Congress and the president can also block the admission of new states. Most prominently, Congress rejected the Tyler-Texas treaty of 1844 for the annexation of Texas Republic into the Union. To circumvent the supermajorities required in the Senate to approve a treaty, President John Tyler and then newly elected President James Polk had Congress annex Texas through a joint resolution, which required only a simple majority. In 1866 President Andrew Johnson vetoed the admissions of Colorado and Nebraska; Congress overrode Johnson's veto of Nebraska but did not admit Colorado until 1876, under the Grant administration. More generally, the Republican-dominated Senate used its power during and after the Civil War to decide when to admit or delay the admission of new states into the Union. By so doing, the Republicans were able to maintain their control of the Senate. So even with a rough balance between the Democratic and Republican parties in the latter half of the nineteenth century, the Republican party was able to keep its Senate majority and, accordingly, to dictate who was being appointed to federal offices and ensure that the institutions established during the Civil War and in the Reconstruction era would remain in place.

Although Congress can admit new states consistent with its authority under Article IV, it cannot itself create new states. States have to arise from the people of separate political communities, with defined territorial boundaries and written constitutions establishing republican governments. Twenty-two states had independent governments before becoming part of the Union (the original thirteen states, Missouri, Michigan, Oregon, Kansas, Minnesota, Nebraska, Vermont, Texas, and West Virginia). The other twenty-eight states acquired new governments to replace their existing territorial and other governments ( such as California's military government, Kentucky's own state government in place of that of Virginia's, and Maine's own state government replacing that of Massachusetts ) once they were admitted into the Union.

Vermont, Kentucky, Maine, and West Virginia are the only states to have been formed out of existing states. And West Virginia stands as the only exception to Article IV's provision that new states cannot be formed out of existing states without the approval of the state legislature that exercises jurisdiction. The people of northwestern Virginia, not wanting to secede along with Virginia, formed their own government and petitioned the Republican Congress for admission as a separate state in 1863.

Congress's power to admit states allowed the United States to expand from coast to coast, into the Arctic, and halfway across the Pacific Ocean. This geographic expansion further enabled the United States to prosper and become a world power. At the same time, the admissions clause enabled Congress to monitor the quality of the federal union. Congress was able to time the admission of states so as to balance northern and southern states in the antebellum years, and Republicans were able to see to it that the Democrats did not regain control of the US government after the Civil War. Congress also used its authority to admit states to preserve cultural and racial norms by denying admission to polygamous Utah until 1896, to Hispanic New Mexico (together with its sister territory, Arizona) until 1912, and to a mostly nonwhite Hawaii (along with Alaska) until 1959.

SEE ALSO Article IV, United States Constitution ; Federal Powers: General ; Territorial Government .


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Bartholomew H. Sparrow
University of Texas at Austin