All samurai had duties and were paid stipends, and from this they had to buy whatever of their equipment wasn’t issued and furnish their household (if they had one). The basis for the economy was rice, and a unit of rice that could feed a man for a year, called a koku, was the universal measure of wealth. Fiefs and estates were described in the terms of how many koku of rice they produced. One koku is 120 litres. The lowest samurai received a little less than a koku (assuming his meals were all on his lord’s estate’s books).
Middling lords, and castle commanders, might receive a stipend of several hundred koku, and with that he had to pay the samurai in his service, supply his garrison, feed his horses, pay his servants, etc. For convenience sake, hard cash was used to make payments, but ultimately it was a rice-based economy. Even the Takeda of Kai, who sat on the most valuable gold mines in the nation, needed rice to feed their soldiers.
Medieval people were particularly vulnerable to weather. They depended on a subsistence economy, had limited storage facilities, and lacked the infrastructure to move food staples around quickly. Severe, destructive weather events could mean the difference between eating and starving, and severe winters, such as those of 873-874 or 939-940 [C.E.], caused high mortality among both humans and animals and resulted in widespread famine.
…The wine of ancient Greece did not taste anything like the wine we know today. It was thick like syrup, and was often heavily flavored with honey, thyme, aloes, and juniper berries. Most people today would find it awful. Even then they had to water it down to avoid toxic intoxication….
We can dimly make out what seems to have been an agricultural revolution in al-Andalus during this period [circa 1000 C.E.]. An increase in productivity was made possible by more intense exploitation of the land. Irrigation, in particular, enlarged the growing season of the year—you can raise four vegetable crops a year on well-tended irrigated land in Mediterranean Spain—and eased dependence on unpredictables such as the weather. Higher and more stable incomes were the result, and with greater prosperity came greater confidence….
More varied crops did more than just diversify gastronomy. (Think of the bleakness of a world without lemons or spinach.) A better, more varied diet means a healthier population. Hard wheat, the main constituent of pasta, grows in drier conditions than soft (bread) wheat and stores for a prodigiously long time because of the low water content of the grain. Al-Razi (d. 955) tells us that around Toledo it would keep in store without decay for upwards of sixty years; it was transmitted in inheritance from father to son like other property. Crops such as this helped to stave off the threat of famine. Prosperity meant earlier marriage, larger families, diversification, opportunity, leisure.