Around 13001350 the Medieval Warm Period gave way to the Little Ice Age. The colder climate resulted in agricultural crises, the first of which is known as the Great Famine of 1315-1317. The demographic consequences of this famine, however, were not as severe as the plagues that occurred later in the century, particularly the Black Death. Estimates of the death rate caused by this epidemic range from one third to as much as sixty percent. By around 1420, the accumulated effect of recurring plagues and famines had reduced the population of Europe to perhaps no more than a third of what it was a century earlier. The effects of natural disasters were exacerbated by armed conflicts; this was particularly the case in France during the Hundred Years' War.

Answer this question, if possible (if impossible, reply "unanswerable"): When did the Medieval Warm Period start?
unanswerable