There are several factors in the host country and the country of origin that might cause people to emigrate. Pre-existing historical contacts and a favourable economic situation in the country of destination are amongst the primary elements to influence migrants’ choices. This chapter will examine the political and economic developments in England, and in Flemish and Brabantine cities before the mid fourteenth century, and how they created the conditions for the migration of textile workers. It will be argued that the migratory process was driven by the prior intensity of trade relations, the existence of communication and transportation links, and the relative frequency of travel between the countries, as well as the political situation, which led to some involuntary migration too.