Youth gangs and the myriad of problems associated with them were once thought to involve a relatively small number of major urban areas whose gang troubles mirrors those of the stereotypical West Side Story scenario. Isolated, under-privileged, youth involved with petty crime and "intimate" physical force played-out only amongst themselves. No longer is this the case. Since 1980, the United States has seen a proliferation of youth gangs. The number of cities with gang problems has increased. This has fueled the public's fear of gangs and enlarged their possible misconceptions about gang problems.
Youth gangs are generally believed to have first appeared in Western Europe or Mexico. The reason for the emergence of gangs in the United States is uncertain, as is the exact date. The earliest recorded incidence of youth gangs dates back to 1783 or towards the end of American Revolution. Social upheaval, displaced families, and a new economy may have caused this birth of a new sub-culture taking form. Youth gangs may have emerged spontaneously from pre-teen social groups or as a response to the industrialization of American culture (Block, 1996). Another theory is that youth gangs first emerged following the mexican migration into the American southwest following the Mexican Revolution in 1813. Mexican youth encountered difficult social and cultural adjustment in America coupled with extremely poor living condition in the southwest. Their organization of gangs and the criminal activity that followed stemmed from a need for survival and support. Schools were few and inadequate and menial jobs as we know them today were non-existent (Moore, 1978). By the early to mid 1800's gangs started to spread to the industrialized Northeast region of the United States. Gangs flourished in large urban cities such as New York, Boston, Philadelphia and particularly Chicago. Migration and population shifts within the United States reached peak levels during this time and the major cities were magnets for rural and immigrant families seeking employment opportunities. Gang activity, level of violence and proliferation seem to be directly related to population shifts within American society. Cultural, societal and economic changes in the United States influence gang activity. In the United States, gang growth and it's highest activity has happened during four distinct periods in history: the late 1800's, the 1920's, the 1960's and the 1990's (Curry, 1988).
In the past youth gangs were largely influenced by the availability of exploitable sources of money. In the modern era youth gangs have been greatly effected by increased mobility, the use of deadlier weapons and the