underground coal mining: see coal mining.

underground: see guerrilla warfare.

Underground Railroad, in U.S. history, loosely organized system for helping fugitive slaves escape to Canada or to areas of safety in free states. It was run by local groups of Northern abolitionists, both white and free blacks. The metaphor first appeared in print in the early 1840s, and other railroad terminology was soon added. The escaping slaves were called passengers; the homes where they were sheltered, stations; and those who guided them, conductors. This nomenclature, along with the numerous, somewhat glorified, personal reminiscences written by conductors in the postwar period, created the impression that the Underground Railroad was a highly systematized, national, secret organization that accomplished prodigious feats in stealing slaves away from the South. In fact, most of the help given to fugitive slaves on their varied routes north was spontaneously offered and came not only from abolitionists or self-styled members of the Underground Railroad, but from anyone moved to sympathy by the plight of the runaway slave before his eyes. The major part played by free blacks, of both North and South, and by slaves on plantations along the way in helping fugitives escape to freedom was underestimated in nearly all early accounts of the railroad. Moreover, the resourcefulness and daring of the fleeing slaves themselves, who were usually helped only after the most dangerous part of their journey (i.e., the Southern part) was over, were probably more important factors in the success of their escape than many conductors readily admitted. In some localities, like Philadelphia, Cincinnati, Wilmington, Del., and Newport, Ind. (site of the activities of Levi Coffin), energetic organizers did manage to loosely systematize the work; Quakers were particularly prominent as conductors, and among the free blacks the exploits of Harriet Tubman stand out. In all cases, however, it is extremely difficult to separate fact from legend, especially since relatively few enslaved blacks, probably no more than a few thousand a year between 1840 and 1860, escaped successfully. Far from being kept secret, details of escapes on the Underground Railroad were highly publicized and exaggerated in both the North and the South, although for different reasons. The abolitionists used the Underground Railroad as a propaganda device to dramatize the evils of slavery; Southern slaveholders publicized it to illustrate Northern infidelity to the fugitive slave laws. The effect of this publicity, with its repeated tellings and exaggerations of slave escapes, was to create an Underground Railroad legend that correctly represented a humanitarian ideal of the pre-Civil War period, but that strayed far from reality. The pioneer study is W. H. Siebert, The Underground Railroad from Slavery to Freedom (1898, repr. 1968); for an extensively revised account, see Larry Gara, The Liberty Line (1961).

Underground railway system used to transport passengers within urban and suburban areas. The first subway line, 3.75 mi (6 km) long, opened in London in 1863 and carried 912 million passengers in its first year. The first electrified subway opened in 1890 in London (where it is called the underground or tube). Subways opened in Budapest in 1896 (the first on the European continent), Boston in 1897, Paris in 1900 (where it is called the métro), Berlin in 1902, New York in 1904, and later in Madrid (1919), Tokyo (1927), and Moscow (1935). Improvements in systems built from the 1970s on (including San Francisco, Washington, D.C., and Los Angeles) include computer technology to run subway trains by remote control, and refinements in track and car construction for faster, smoother, and quieter rides.

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or Underground

Clandestine groups opposed to Nazi rule in German-occupied Europe in World War II. The groups included civilians who worked secretly against the occupation and armed bands of partisans or guerrilla fighters. Resistance activities ranged from assisting the escape of Jews and Allied airmen shot down over enemy territory to committing sabotage, ambushing German patrols, and sending intelligence information to the Allies. Resistance groups were not always unified; in some countries, rival groups divided along communist and noncommunist lines. However, in France the clandestine National Council of the Resistance coordinated all French groups, which gave support to the Normandy Campaign and participated in the August 1944 uprising that helped liberate Paris. Resistance groups in other northern European countries also undertook military actions to help the Allied forces in 1944–45.

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Secret system in northern U.S. states to help escaping slaves. Its name derived from the need for secrecy and the railway terms used in the conduct of the system. Various routes in 14 states, called lines, provided safe stopping places (stations) for the leaders (conductors) and their charges (packages) while fleeing north, sometimes to Canada. The system developed in defiance of the Fugitive Slave Acts and was active mainly from 1830 to 1860. An estimated 40,000 to 100,000 slaves used the network. Assistance was provided mainly by free blacks, including Harriet Tubman, and philanthropists, church leaders, and abolitionists. Its existence aroused support for the antislavery cause and convinced Southerners that the North would never allow slavery to remain unchallenged.

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