The idea of sending a colony of persons of African descent from the United States to Africa appears to have first occurred to the Rev. Samuel Hopkins and the Rev. Ezra Styles of Newport, R. I. They issued a circular on Aug. 31, 1773, in which they invited contributions toward the founding of such a colony. A contribution was made Feb. 7, 1774, by a society of ladies of Newport, and aid was received from Massachusetts and Connecticut. The revolutionary war interrupted these labors. In 1784 and 1787 Dr. Hopkins renewed his efforts to obtain funds for colonization, and endeavored to make an arrangement by which free blacks from America might join the English colony of Sierre Leone. Not being successful in this, he published in 1793 an appeal in which he urged that the plan of colonization ought to be adopted in the several states and by the federal government. He continued to agitate the subject from time to time until his death, Dec. 20, 1803. The first emigrants sent from the United States were a company of 38 colored persons who were taken from New Bedford to Sierra Leone in 1815. The subject of colonization in Africa was brought before the legislature of Virginia in 1800-'2, but no definite results were obtained.

Samuel J. Mills, Robert Finley, Elias B. Caldwell, and Francis S. Key were conspicuous for their exertions in drawing attention to the plan; and a meeting was held at Princeton, N. J., in the autumn of 1811, to consider the steps to be taken for the organization of a colonization society. A second meeting was held Dec. 23, and the constitution of the "American Colonization Society" was adopted Dec. 28. The first officers were elected Jan. 1, 1817, and the same year Samuel J. Mills and Ebenezer Burgess were sent to Africa to select a site for the colony. They chose Sherbro island and the coast adjoining. Mills died on the return voyage. In March, 1819, congress appropriated $100,000 for the purpose of carrying back to Africa such slaves as should be surreptitiously imported. Under the construction which was put upon this law by President Monroe, part of its design was that a residence should be provided in Africa for the agents of the United States and such slaves as were sent back. For this purpose it was necessary that emigrants should be sent out and a settlement made. The formation of such a settlement being the object for which the colonization society was organized, the government and the society determined to cooperate.

The society designated 88 persons as emigrants, and the government chartered a ship, appointed an agent, and placed $30,000 at his disposal. The ship sailed Feb. 6, 1820. The emigrants were to erect huts for the reception of at least 300 recaptured Africans, and cultivate land for their own support. They did not succeed in establishing themselves on Sherbro island, but in April, 1822, made their settlement at Cape Mesurado, between Sierra Leone and the Ivory coast. The society was represented in the colony by Jehudi Ashmun, who arrived there Aug. 9, 1822. Under his leadership the colonists repulsed on Nov. 11 an attack made by 800 natives, and a second assault on Dec. 2, made by about twice the number. The agents of the United States were instructed not to attempt to exercise any power or authority over the colonists, and the government of the colony was assumed by the society. The board of managers adopted, on Jan. 26, 1820, a constitution for the colony, by which the powers of government, legislative, executive, and judicial, were vested in the society's agents. Ashmun undertook to exercise the powers which were conferred upon him, but the colonists were not disposed to acquiesce, and Ashmun for a time abandoned his undertaking.

The United States government and the colonization society deputed Ralph R. Gurley to investigate the condition of affairs. He had a conference with Ashmun, the result of which was that in 1824 a plan for the civil government of Liberia was adopted, by which the society retained the ultimate decision on all questions of government. A more formal constitution was adopted Oct. 22, 1828, by which a considerable part of the civil power was secured to the colonists. This constitution was changed from time to time, and the share of the people in the government was made greater and greater. After the death of Governor Buchanan in 1841, Joseph J. Roberts, who had previously held the office of lieutenant governor, through election by the people, was appointed governor by the society.

A legislature was in existence, but its laws were subject to the veto of the society, as were also all treaties made by the colony. Several valuable tracts of land had been acquired by treaties made with native chiefs, and duties had been imposed on goods imported. British subjects who traded on the coast included within the territory of the colony landed goods without paying duties; and when their goods were seized by the government of Liberia, they applied to the British government for redress. The British authorities applied to the government of the United States, and were informed that Liberia was an independent political community, and not a colony of the United States; whereupon the British took the ground that Liberia had no existence as a nation, inasmuch as its powers were derived from an association of private individuals, which did not possess and could not impart any political authority; and that the levying of imposts being a prerogative of sovereign power, the rights of British subjects to free commercial intercourse would be enforced by arms.

In this emergency the directors of the society, in January, 1846, surrendered such governmental power as they still retained, and recommended the colony to publish to the world a declaration of its true character as a sovereign and independent state. The colonists appointed delegates, who on July 26, 1847, adopted a declaration of independence and a new constitution. In 1848 the independence of the republic was acknowledged by Great Britain and France, and afterward by most of the powers of Europe and America. The Maryland colony, which had maintained a separate existence, united in 1857 with Liberia. The credit therefore is due to the colonization society of having been mainly instrumental in the foundation of Liberia, and of having guided its destinies until it became a self-supporting state. Since relinquishing all direct control over the government of Liberia, the colonization society has continued to send out emigrants, and to furnish them with provisions and temporary dwellings, and has aided in developing commerce and agriculture. It has also labored for the dissemination of Christianity, and for the promotion of education and the general welfare of the country.

The abolition of slavery has not by any means put an end to the usefulness of the society; on the contrary, since that event the number of applications for passage to Liberia has very much increased. The receipts of the society from its foundation to Jan. 1, 1872, were $2,364,648 47, and those of the auxiliary societies more than $400,000. The whole number of emigrants which had been sent out at that date by the parent society was 13,598; and 1,227 had been sent out by the Maryland society, and 5,722 recaptured Africans by the United States government. The presidents of the society have been Bushrod Washington, Charles Carroll, James Madison, Henry Clay, and J. H. B. Latrobe. (See Liberia).