High middel ages - causes of growth?

Well, the cause of population growth is still being debated, of course.  In fact, in certain circles, it is still debated whether or not there actually was population growth.

In general, there are a number of theories:

M.M. Postan, in his Medieval Agrarian Society in its Prime: England takes a very Malthusian (and for years, influential) perspective.  He states that a rapid 'colonization' of the excess land in Europe lead to a great supply of agricultural production, until the land was used up and left exhausted.  This 'land hunger,' he claims, was enough to sustain the population of England in the thirteenth century equal to the amount in the eighteenth century.  It was only after the population expanded too fast that it overworked its own resources.

Conversely, Bruce Campbell, in his Arable Productivity in Medieval England:  Some Evidence from Norfolk, takes a different stance.  He criticizes the Postanian perspective by attempting to show that one cannot infer from the specific to the general in terms of population growth.  To prove this, he cites the example of the estates of Norfolk, which themselves suffered independent growth or decline simultaneously.  He further goes on to show that environmental factors - soil quality, seed yields, etc - determined growth where there was some.

Now, the article by Richard Easterline, Malthus Revisited: The Economic Impact of Rapid Population Growth attempts to go in a third direction.  Easterline basically thought that improving economic conditions (from the Commercial Revolution of the twelfth and thirteenth centuries) meant that there was population growth because of the availability of these new opportunities, and that as the population grew, enough intelligence was generated to in turn develop more and more opportunities for expansion (in land, commerce, etc).  In this regard, he takes more of a Boserupian stance than a Malthusian one.

So, I hope that wasn't too much, and hopefully answered your question somewhat.  Good luck with your exam.

That's probably true, although it's a very Wrigley and Schofield-ian perspective (I'm not surprised that their theory would be dominant in textbooks).  They basically state what you just said, that better economic conditions led to earlier marriages and more children, and less of so when there were poorer times.  In fact, Wrigley was knighted for developing this theory.

You're right about the chronology debate, too.  The authors I mentioned certainly peg the growth rate at varying times, and then there's Barbara Harvey, who says essentially that there was no real population decline before the Black Death - unlike Postan and some others.

What class is this for?  It seems almost like an economic history course.

Bartlett in his book Conquest, Colonisation and Cultural Change in the European Middle Ages, considers the population explosion of the High Middle Ages to be a direct consequence of intensive rural administration and cultivating previously derelict land. The early medieval period saw power and administration decentralised, falling into the hands of local magnates such as abbots and knights. The gravity of power and focus of the rulers was no longer chiefly on the cities as it had once been in antiquity, micromanagement of agricultural expansion saw swamps drained, forests felled and settlements properly fortified against attack.

Unlike in the Late Roman Period, where the centralised Roman army had great difficulty stamping out roving bands of armed predators throughout the countryside, the feudal system provided even small villages with a form of localised defence which was typically quick to respond. In case of attacks which were too formidable to defend against, the local ruler could usually move most valuable property inside a properly defensible bastion and call upon his feudal superior for reinforcement. This improved form of localised security ensured less devestation overall than occurred in the Late Roman period.

Effective local security and intensive micromanagement of agriculture provided the environment for population growth, with the High medieval period seeing the population of Northern Europe surpass that of the Mediterranean world for the first time.