Demographic Crises
Lightning Strikes Twice
As devastating as the Black Death was, it actually was of a great benefit to many (not all!) of the survivors. The nobility had it tough because of a shortage of labor, increasing wages and increasing costs. The common folk, though, found more jobs, better wages, and their costs tended to stay stable or even decline, for their main costs were things like grain, which was plentiful in the 1350s.
If you survived the plague, you could breathe a sigh of relief. You'd survived. You had higher wages, or more land, or a better job. A new life, maybe. Things might be bad locally, like they were in northern France, what with having your king captured and all, but in most places people discovered they were actually pretty well set. Earthquake or planetary conjunction or divine punishment, whatever it was, it was over now.
Then, incredibly, in 1360, the Black Death returned. In some ways, it was even more nightmarish, because it hinted that the nightmare wasn't really over. The chroniclers called this secunda pestis, the Second Plague, but they also called it the Children's Plague pestis puerorum, for it struck most fatally at the young. People recognized it at once as a return of the Black Death and the impact was psychologically devastating. The mortality was not so devastating as the first time, but the fact that it struck mainly at the young was unnerving. As before, it spread across most of Europe, lasting through 1361.
The Third Plague
A mere eight years passed before it came again, the tertius pestis. By the time of the third plague, Europeans were beginning to understand that this was a permanent visitor and that, if it were the scourge of God, it was a scourge that could not be alleviated. The tone of the reports of the "Third Plague" are more matter-of-fact. Losses in these subsequent plagues were more on the order of five to ten percent of the total population of Europe, but our sources are extremely skimpy and it's certain that some areas suffered more than others.
The third plague is a good candidate for being as important or even more important than the original outbreak, not because of the sheer numbers of deaths but because of the cumulative effects. As mentioned, we have good evidence of recovery in the wake of the original plague. The example of the Great Famine would suggest that, had this been the only outbreak, Europe would have recovered, probably within a generation or two. The second outbreak dealt a severe blow to the recovery, but the third, which was the most severe since the original and which was somewhere in Europe from 1369 (in the north) to 1374 (in the south), the third led to permanent change.
It is really only with the Third Plague that we see severe economic dislocation, as manifested in attempts at wage and price controls, for example. It's only in the wake of this plague that we see permanent shifts in landholding patterns (in England, at least). It's in the 1370s that it starts to become evident that the decline in urban populations, and when we start to get noticeable numbers of abandoned villages.