The trade union movement in the United States originated during the early years of the republic. Skilled workers were the first to organize and form unions. During the 1790's unions were formed by carpenters and shoemakers of Philadelphia, tailors of Baltimore, the printers of New York City, and groups in other large cities. Sporadic work stoppages occurred during the early decades of the 19th century, although strike leaders were fined and imprisoned for what was termed "conspiracy to raise wages."

In 1827 several trade unions in Philadelphia banded together to form the Mechanics' Union of Trade Associations, the first U.S. labor organization to unite workers in different crafts. Besides acting to raise wages and improve working conditions, these united labor organizations espoused certain social reforms, such as the institution of free public education, the abolition of imprisonment for debt, and the adoption of universal manhood suffrage. Perhaps the most important effect of these early unions was their introduction of political action. Organizing and growth in the labor movement was stimulated by the decision of a Massachusetts court in 1842 (Commonwealth v. Hunt), stating that strikes to improve labor conditions were lawful and were not criminal conspiracies.

In December 1886, The Federation of Organized Trades and Labor Unions of the United States and Canada and The Knights of Labor merged together and formed the American Federation of Labor (AFL). They elected Samuel Gompers, then president of the Cigar makers International Union and of the Federation of Organized Trades and Labor Unions, as its first president. The initial membership of the AFL was an estimated 140,000 workers grouped into 25 national unions.
The AFL represented a form of so-called business unionism. This basically meant that it was a loose confederation of unions, each with exclusive rights to deal with the workers and employers in its own field. Instead of campaigning for large sweeping reform programs that were so popular in that day, the AFL confined itself to the pursuit of specific, attainable goals, such as higher wages and shorter hours. The AFL prided itself in not identifying itself with any one political party or movement, but instead adopted the policy of urging its members to support candidates that were considered labor friendly regardless of party affiliation.

During the 1890's several of the AFL unions, including those in the printing and the building trade workers unions, finally achieved the long-sought after goal of the 8-hour work day. Nevertheless, the movement moved along slowly until the 20th century. Prevailing opinions were still hostile towards organized labor, and the fact that both government and the courts acted to restrain union activity didn't help matters much either. The depression in the early 1890's and a few disastrous strikes stunted the growth of the union as well. In the historic strike(1892) at the Homestead Mill of Carnegie Steel in Pittsburgh, large numbers of private detectives and national guardsman were used against the striking workers to the extent that the strike was lost and the union nearly destroyed. In 1894 striking railroad workers against the Pullman Company were defeated by an injunction issued under the Sherman Antitrust Act of 1890. What that Act basically said was that it was illegal to restrain trade. Employers used this tactic with increasing frequency, and were very effective with it.

By 1904 more than 2 million workers were members of trade unions. Almost 1.7 million belonged to the AFL. By this time many industries including construction, publishing, glass, ceramics, coal, and railroads had begun to accept collective bargaining with unions. In 1913 the U.S. Congress created the Department of Labor, assuring that the problems of labor would receive its due consideration. Massachusetts enacted the first minimum wage law in the United States in 1912. These achievements contributed to a sharp rise in membership. By 1920 trade unions had about 5.1 million members, of which 80 percent were in the AFL.

During the 1920's the trade union movement was on the decline, due largely to the depressions of the 20's and 30's. The election of Franklin D. Roosevelt to the Presidency in 1932 marked the beginning of stimulating new growth in the union movement. In June of 1933 the National Industrial Recovery Act was enacted. One of the most controversial sections of this law stipulated that "employees shall have the right to organize and to bargain collectively through representatives of their own choosing, and shall be free from the interference, restraint, or coercion of employers....in the designation of such representatives." In May 1935 the Supreme Court ruled this to act to be unconstitutional but 2 months later congress enacted the National Labor Relations Act which provided even stronger government support for organized labor.