Used generally to describe a series of economic events in the late 15th through the mid-17th century, the Price Revolution refers most specifically to the high rate of inflation that characterized the period across Western Europe.
As early as the 16th century, it was thought that this high inflation was caused by the large influx of gold and silver from the New World. According to this theory, there was simply too much money for the amount of available goods.
In reality, many things contributed to the Price Revolution. Chief among them was the fact that Europe's population grew after the devastation of the Black Death, but rural populations did not keep pace with urban populations. There were more people to feed, but proportionately fewer producers of staple foods. Increased trade and availability of manufactured and luxury goods, especially in the 16th and 17th century, had also encouraged many landowners to convert their tenants' payments from produce to cash. Initially, this helped the wealthy to accumulate more of the trappings of wealth.
As the inflation rate grew, however, those landlords who received payment in cash found themselves in financial straits. They often took extreme measures to combat the problem -- measures that would add to social unrest and ultimately to a worsened financial position for themselves and their tenants. In England, for example, many lands held as common lands (pastures, fields, etc.) were enclosed so that only the landlord could graze his animals. This forced his former tenants either to pay increased rents, which was close to impossible, or to leave their own farms. An increase in vagrancy meant more brigandage, a movement to the towns in search of employment and, where no employment could be found, an increase in urban poverty and crime.