In a globalized world, migrations for economic reasons are driven both by demands for work and demand for labor. One of the most common economic migrations, historically and today, has been from rural to urban areas.
In the Middle Ages, the saying ‘City air makes one free' referred to a custom where if a runaway serf could stay in a city for a year and a day without being captured he would be considered legally free. Then as now the economic activities taking place in urban areas required labor. Later, during the Industrial Revolution, millions of people moved from agricultural situations to urban work centers. During what was known as the Enclosure Movement, when properties were fenced in so the owners could begin large-scale agriculture, some people were driven off these lands that had been traditionally worked in common.
Read about migrations during the Industrial Revolution here:
https://www.bbc.co.uk/bitesize/guides/zqpvxsg/revision/3
Today the movement from rural to urban areas for economic reasons continues. One of the most prevalent modern migration movements has been from Mexico to the United States (although with anti-immigration laws and the current slowdown in US construction, this movement has presently reversed), with about 12 million Mexicans coming to the United States in the past four decades. Much of this immigration into the United States has been illegal and tacitly accepted by US businesses seeking inexpensive labor. Push factors for Mexican immigration to the United States have included a debt crisis followed by a 50% unemployment rate, and, recently, drug trafficking-related violence, while pull factors include a higher level of economic opportunity and a more stable political environment.
Read more about Mexican immigration here:
Movement based on economic motives in the case of forced migration has not always been from rural to urban areas. Between the 1500s and 1860, the forced migration to the Americas of approximately 12 million Africans for plantation labor took place.
Fortunes from sugar, cotton, and rice were made from the unpaid labor of these immigrants forced into slavery; some of these fortunes were used to finance further business development.
Read about African-American migrations, from impressment into slavery to the search for a better life, here:
http://www.inmotionaame.org/migrations/index.cfm;jsessionid=f8302116721355565932581?bhcp=1
Political factors also drive migration. The Jewish diaspora of 587 B.C.E. was a forced migration. After the Babylonians conquered Judea and destroyed the temple at Jerusalem, they exiled part of the Jewish population to Babylonia (today's southern Iraq), while another part of the population fled to Egypt and settled in the Nile Delta region of Egypt. Ultimately this dispersion continued over the centuries and led to the settlement of Jewish populations around the world: the USA, Canada, Argentina, and Brazil today are home to some of the largest Jewish populations. Another political migration began in 1959, after the Cuban revolution led by Fidel Castro. From 1960 to 1976, 750,000 Cuban refugees were admitted to the United States.
Read about Cuban (and Puerto Rican) immigration here:
Originally, theories of human geography focused on environmental determinism, which held that characteristics of people and cultures are due to the influence of their natural environment. This view was followed by the theory of regional geography, which explained movement according to descriptive information about places and the way territories can be defined by rivers or mountain ranges. A third way of studying these relationships is quantitative. Finally, humanist geographers focus on people's sense of, and relationship to, their environment.
