Archeologists digging in ruins in Pakistan have found traces of cotton fabrics and cotton string dating back to 3000 B.C. Excavations in Peru have uncovered cotton cloth dating back to 2500 B.C. Cotton fabrics were described by the Greek historian Herodotus in 500 B.C.

Cotton cultivation was brought from North Africa to Spain in 712 A.D. by the Moors. There, cotton manufacture in Europe began and gradually spread northward. By 1400, central Europe and the Low Countries were making fine fabrics with cotton imported mainly from the Middle East, where the best cotton was grown.

Early Spanish explorers in the New World found widely scattered native cultures using cotton cloth. The first cultivation of cotton by Europeans in the New World was by the Spanish in Florida.

Edward III of England brought Flemish weavers to Manchester in the 14th century. Their cloth soon became famous. Before 1700, most weaving was done in the home. In the mid-18th century, the Industrial Revolution contributed many inventions to the cloth manufacturing trade, and factory production of cotton goods developed.

British colonists found that the climate of the southern American colonies was ideal for cotton growing. But because there were no mills in America, the raw cotton was sent to England. Cloth was woven there and resold in the colonies. The secrets of cotton manufacturing machinery were carefully guarded by the British to preserve this monopoly.

The cotton textile industry began in the United States in 1790, when Samuel Slater, who had worked in English mills, was able to reconstruct from memory the cotton-manufacturing machinery, at Pawtucket, Rhode Island. The growth of American mills, mostly run by water power, was rapid. Eli Whitney invented the cotton gin in 1793. Before the invention of this machine, cottonseed was separated from the lint by hand—a very slow process. One person could clean only about one pound (0.45 kg) of cotton a day. Whitney's gin could clean 50 pounds (23 kg) a day, making possible the widespread use of cotton cloth.

The South, with its slave labor, produced cotton cheaply and came to be called the Cotton Kingdom. Huge plantations of 2,000 acres (800 hectares) or more were the basis for the cotton economy. Most of the people of the South depended, either directly or indirectly, upon cotton for their living.

Cotton was one of the contributing factors leading to the Civil War. Plantation owners bitterly opposed a high tariff that protected the products of northern factories but not the raw materials exported from the South. "Cotton is king" became a Southern slogan, the planters erroneously believing that the North could not carry on a war without Southern cotton.

Few plantations could survive without slave labor and many were broken up into small farms. They were worked by sharecroppers, or share tenants. The tenant paid the landlord a portion, usually a half, of the value of the crop for use of his land. The tenant supplied his labor and sometimes half the fertilizer, and generally received half the crop. This system was inefficient and the sharecroppers were often extremely poor. Nonetheless, it survived until the South began to become industrialized, during and after World War II. Since then, most of the former sharecroppers have left the farms to work in factories.

There have been two other major changes in the cotton industry since World War II. One is the greatly increased use of mechanical planting and harvesting equipment, resulting in greater efficiency. The second is the decline in the total acreage devoted to cotton. One reason for this decline is that synthetic fibers, paper, and other cotton substitutes have come into wide use. Another is that foreign production has increased greatly. A third reason is that many farmers have found it more profitable to diversify their crops. Instead of devoting all their land to cotton—which is subject to wide variations in price—they also raise other crops as well.

Since about 1920 the cotton farmer has been receiving increasing attention from the federal government and private organizations. Agricultural colleges and the U.S. Department of Agriculture have developed better varieties of cotton and are constantly seeking better ways to grow and market the product. The National Cotton Council of America was organized in 1938 for the purpose of increasing consumption of cotton, cottonseed, and their products. Its program of research and promotion is financed by all branches of the cotton industry.

Federal agencies offer various types of financial aid. The Commodity Credit Corporation (organized in 1933) uses facilities of the Agricultural Stabilization and Conservation Service (1961) to support cotton prices through loans and purchases. Various federal programs of acreage control have also been used since the early 1930's in efforts to keep supply in line with demand. The Farmers Home Administration (1946) offers long-term, low-interest loans to farmers unable to secure private credit for operating expenses, farm ownership, housing, improvements, and other purposes. The Federal Crop Insurance Corporation (1938) insures crops against loss from causes beyond the farmer's control, such as weather, insects, and disease.

The cotton plant belongs to the genus Gossypium of the mallow family (Malvaceae). Upland cotton is G. hirsutum; Sea Island and Egyptian cottons are G. barbadense; Asiatic cottons are G. arboreum and G. herbaceum; Peruvian cotton is G. peruvium; Mexican cotton is G. mexicanum; Jamaica cotton is G. punctatum.