Organic Act

An Organic Act, in United States law, is an Act of the United States Congress that establishes a territory of the United States or an agency to manage certain federal lands. In the absence of an organic law a territory is classified as unorganized.

The first such act was the Northwest Ordinance, passed in 1787 by the U.S. Congress of the Confederation (under the Articles of Confederation, predecessor of the United States Constitution). The Northwest Ordinance created the Northwest Territory in the land west of Pennsylvania and northwest of the Ohio River and set the pattern of development that was followed for all subsequent territories. The Northwest Territory covered more than 260,000 square miles and included all of the modern states of Ohio, Indiana, Illinois, Michigan, Wisconsin, and the northeastern part of Minnesota.

The District of Columbia Organic Act of 1801 incorporated Washington, D.C. and placed it under the exclusive control of the United States Congress.

The Organic Act for the Territory of New Mexico was part of the Compromise of 1850, passed September 9, 1850. Primarily concerned with slavery, the act organized New Mexico as a territory, with boundaries including the areas now embraced in New Mexico, Arizona, and southern Colorado.

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