Beginning in the mid 1600's Earth entered into a mini-ice age. 1815 was known as the "year without a summer" and snow fell in many European countries during the summer months. The year without summer was believed to be the result of a major volcanic eruption, Mount Tambora. Although the exact cause of the mini ice age is unknown, scientists speculate that the low temperatures correspond with

very low sunspot activity

Reason:

Due to the low temperature and very high rainfall, the Crop could not grow properly in European nation. Due to this , the people devoid of food reached at the verge of dying. After certain point of time there was feminine.  The effect were so devastating that these lasted even after the winter season was over. Lack of food raised the price of food item

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