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Historical records show that there was a period of very long and cold winters over a 70-year period from about 1645 to about 1715. Meteorologists call this time the little ice age (see addendum). Glaciers in the Alps advanced. The North Sea froze over. Later examination of astronomical records showed that astronomers reported seeing almost no sunspots during that period. Sunspots are relatively dark spots on the surface of the Sun. They are similar to storms on Earth. They are associated with the solar wind, which causes the northern lights (aurora borealis) on Earth. Sunspots normally increase and decrease in number over an eleven (varies from 7 to 16 years) year cycle (22 years actually, because the magnetic fields of the sunspots reverse every 11-year cycle, and so are back where they started after 22 years). During the little ice age, the northern lights were almost never seen, and some people considered them a myth. This relationship between sunspots on the sun and weather on earth has been confirmed by study of other periods of sunspot minimums, each of which has caused colder weather. And droughts seem to occur about every 22 years. The relationship is not well understood.
Addendum:
A few brief (lasting a few years) cold spells have been associated with large volcanic eruptions, such as Tambora (1816?) and Krakatau (1883). Incidentally, there was a movie about the Krakatau (also called Krakatoa) eruption, called Krakatoa, East of Java. Krakatau is west of Java. Read eyewitness accounts of the eruption of Krakatoa.
Estimates of when the little ice age began and ended differ greatly, from author to author. Brian Fagan, in The Little Ice Age, gives the dates as about 1300 to 1850. Before that was the "medieval warm period" in which the waters around Iceland and the southern part of Greenland were almost ice-free. In this scenario, the period from 1645 to 1715 was a particularly cold part of the larger cold period. And this shorter period was also the period of very rare sunspots and northern lights (and southern lights). In the late 1800's, E. W. Maunder and F. W. G. Sporer (Spörer) discovered this fact from examining the records of earlier astronomers. 1645 to 1715 is now called the "Maunder minimum." Later discoveries of old records confirmed the phenomenon. Apparently, the rest of this larger little ice age is not associated with any known lack of sunspots or northern lights.
The little ice age was not just a period of cold and hardship; it involved famine and death.