I'm reading, in my spare time, a book called The Hollow Crown, by medieval scholar Miri Rubin. The book starts with a vivid description of the six-year weather anomoly that manifested itself in wet, cold summers. The crops rotted, cattle and sheep were stricken with mold and fungus diseases, and between 10 and 15 per cent of the people died. It must have been incredibly depressing: the sky never cleared, fields were flooded, and the weakened survivors had to wallow in mud to dig graves for people and livestock. The famine is now fairly obscure. The Black Death, which arrived a generation later, gets far more ink in the texts.
The 1315-21 weather pattern signalled a change in climate from a relatively warm period to the Little Ice Age that ended in 1850. It's as major a weather disaster as the 1920s-1930s Dust Bowl on the Great Plains.