<P> Famines were familiar occurrences in Medieval Europe . For example, localised famines occurred in France during the fourteenth century in 1304, 1305, 1310, 1315--1317 (the Great Famine), 1330--34, 1349--51, 1358--60, 1371, 1374--75 and 1390 . In England, the most prosperous kingdom affected by the Great Famine, there were famines such as in 1315--1317, 1321, 1351 and 1369 . For most people there was often not enough to eat, and life was a relatively short and brutal struggle to survive to old age . According to official records about the English royal family, an example of the best off in society, for whom records were kept, the average life expectancy in 1276 was 35.28 years . Between 1301 and 1325, during the Great Famine it was 29.84 years while between 1348 and 1375 during the Plague, it was only to 17.33 years . The figures do not necessarily mean the average lifespan of an adult, as child mortality was extremely high in pre-industrial societies . </P> <P> During the Medieval Warm Period (the period prior to 1300), the population of Europe exploded compared to prior eras, reaching levels that were not matched again in some places until the nineteenth century--indeed parts of rural France today are less populous than at the beginning of the fourteenth century . However, the yield ratios of wheat, the number of seeds one could eat per seed planted, had been dropping since 1280, and food prices had been climbing . After favourable harvests, the ratio could be as high as 7: 1, but after unfavourable harvests it was as low as 2: 1--that is, for every seed planted, two seeds were harvested, one for next year's seed, and one for food . By comparison, modern farming has ratios of 30: 1 or more (see agricultural productivity). </P> <P> The onset of the Great Famine coincided with the end of the Medieval Warm Period . Between 1310 and 1330, northern Europe saw some of the worst and most sustained periods of bad weather in the entire Middle Ages, characterized by severe winters and rainy and cold summers . The Great Famine may have been precipitated by a volcanic event, perhaps that of Mount Tarawera, New Zealand, which lasted about five years . </P> <P> Changing weather patterns, the ineffectiveness of medieval governments in dealing with crises and population level at a historical high made it a time for little margin for error in food production . </P>

What caused the great famine that began in 1315 ce in europe
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