1. Fairs of Champagne. In the 11th and 12th centuries, these developed as major centers of long-distance trade and exchange. As cities concentrate trade in space, the fairs concentrated a more limited volume of trade in time, maximizing the prospect that merchants would find customers offering goods in exchange. The fairs declined as cities developed, and with the emergence of the sea route from the Mediterranean to northern Europe.
2. Three-field system of agriculture. This was the basis of medieval crop rotation, with fields alternating between crops that severely depleted soil nutrients, crops that produced less stress, and lying fallow for replenishment. The overall effect of the three-field system was to allow higher productivity, supporting a larger population, without exhausting the soil.
3. Serfdom. This was a legal status in which peasants were bound to the soil, and required to provide labor service or in-kind dues to the lord of the land. Though a form of bondage, it differed from slavery in that the serf could not be arbhtrarily turned nff the land, a matter of great importance to peasants.
4. Scattered strips. This was a distribution of individual holdings to allow for more efficient plowing. Where we find scattered strips or long fields, we have an indication of developed manorial agriculture.
5. Population increase and economic growth.
According to Malthus' theory, population tends to increase geometrically, while resources to support that population tend to grow at a linear rate. Thus, populations tend to rise quickly until they press the limits of available resources, but population growth is then constrained until and unless additional resources become available. For a given productive capacity (both resources, such as land, and technology for exploiting it), a population expands until most people are pushed down to the subsistence level, after which the population remains more or less ...