I did find one article discussing measles epidemics in “northwest” Iceland, and while I was searching for 1846, the article said there was another measles epidemic in 1882. There’s not enough information in the article’s abstract to tell me if these are actually the causes of the spikes I found in the chart.
I’ve also found some general information about epidemics of the time, but none specifically referring to Iceland in 1860.
There’s a drop in the US in 1918 from the influenza pandemic. Iceland is pretty small, so similar circumstances might have a more noticeable effect there.
The so-called “Little Ice Age” strongly affected the northern hemisphere for several hundred years. One of the minima was in 1850. The colder climate adversely affected crops, livestock, and living habits (including migration patterns) which possibly contributed to Iceland’s population/life expectancy dips. Also at that time in history, pandemics of diseases like tuberculosis and flu were common. The causal bacteria wasn’t even discovered until the 1880s, if I recall correctly.
My WAG is that a surge in emigration would drive life expectancy up. Immigrants tend to be young so if a bunch of them are leaving, the average lifespan of those who stay home would presumedly rise. Although there might be some complications over the difference between average lifespans and average life expectancy.
I would guess that its mostly a data collection issue. Basically the generators of this plot used what data was available, which may not be completely accurate. With Iceland being a small country, and record keeping being rather sketchy, the data for those years may be quite noisy. I also notice that many of the other countries on that plot at this time had entirely flat life expectancy ratings, which suggests to me that a single value is used to encompass a long stretch of time.
I’d guess this, too. Note that Norway is an outlier in the other direction, and one might expect any climate issues affecting Iceland to affect Norway in the same manner.
Out of interest, what makes you say that record keeping would have been sketchy? Iceland took its first census in 1703, apparently, even ignoring the usual parish record-type things which every country seems to have.
I would guess this isn’t a data collection issue. I did find references to measles epidemics in 1846 and 1882, which might explain those two years, especially if it hit infants particularly hard. I would like some harder confirmation of the linkage, but it does at least make a lot of sense. And I’m not seeing anything specific about 1860, except that it was the final year of a worldwide flu pandemic. Also, I found reference to “the 1860s” being a time when much of the sheep population was lost to disease, and there been several very harsh winters. So perhaps famine was the cause, or one of the causes.
You can look at a bunch of other countries and times and see well known historical events reflected in these changing numbers. The Irish potato famine, the Russian famines of the 30s, China’s Cultural revolution, etc…
It argues infant nutrition was a major factor, in large part because formula feeding was much more prevalent in comparison to other countries of the time. Apparently this made infants much more susceptible to disease, and during epidemics the infant population was devastated. On the very first page it notes that infant mortality in 1846 was 60%.
Malnutrition and diseases are complementary. Dying to pure malnutriotion requires a bacteria-free environmant. Outbreaks of disease are likely to correlate with bad crops.
Great thread, I had just watched Iceland’s population crash on Gapminder and wondered what caused it. The infant mortality answer makes a lot of sense.
One small correction:
The big dip in China’s life expectancy from 1959-1962 was a result of the Great Leap Forward, and not the Cultural Revolution, which came later. While the Cultural Revolution is famous for its blind violence, the agricultural policies of the Great Leap were far more lethal: estimates range from a conservative 25 million to over 40 million dead in just 3 years.