Little Ice Age

A story that’s been making the rounds:

Genocide of Native Americans by European settlers was cause of Little Ice Age

The upheavals following the first contact with Europeans in 1492 is thought to have cut the population of 60 million living across the Americas down to five or six million within just 100 years

The “Little Ice Age” of the 16th and 17th centuries was triggered by the genocide of indigenous people in the Americas by European settlers, new research suggests.

Scientists have long wondered what caused the drop in temperatures so severe that it caused the River Thames to freeze over.

New analysis by University College London (UCL) argues that so many people were slaughtered or died of disease that the amount of agricultural land dramatically reduced, which in turn sucked carbon dioxide (CO2) from the atmosphere.

Known as the “Great Dying,” the upheavals following the first contact with Europeans in 1492 is thought to have cut the population of 60 million living across the Americas down to five or six million within just 100 years. Published in Quaternary Science Reviews, the study found that much of the land previously cultivated by indigenous civilizations would have fallen into disuse, becoming swallowed up by forest and grassland.

It estimates that an area of 56 million hectares, roughly the size of modern-day France, would have been “rewilded” in this way.

The scale of the change is believed to have drawn an amount of CO2 from the atmosphere equivalent to two years of fossil fuel emissions at the present rate.

Professor Mark Maslin, from UCL’s School of Geography, said: “There is a marked cooling around that time which is called the Little Ice Age, and what’s interesting is that we can see natural processes giving a bit of cooling, but to actually get the full cooling – double the natural processes – you have to have this genocide–generated drop in CO2.”

The research team examined historical population data, using it to model the reduction of land devoted to agriculture.

Ed Hawkins, professor of climate science at Reading University, said: “Scientists understand that the so-called Little Ice Age was caused by several factors – a drop in atmospheric carbon dioxide levels, a series of large volcanic eruptions, changes in land use and a temporary decline in solar activity. The drop in CO2 is itself partly due the settlement of the Americas and the resulting collapse of the indigenous population.

“It demonstrates that human activities affected the climate well before the industrial revolution began.”

An interesting theory! But I have some questions. How many Native Americans actually practiced agriculture? And why do cultivated crops put more CO2 into the atmosphere than wild flora? This quite apart from the immense difficulty of determining past population numbers in the absence of a proper census. It would have been good for the article to cite actual data (from ice cores, etc.) about just how much atmospheric carbon dioxide declined in the Early Modern Period.

But as is so often the case with newspaper articles, you have to read all the way to the end to get the real story (which is why I have taken the liberty of reproducing the entire piece). Prof. Hawkins says something completely commonsensical – that the LIA was caused by a variety of factors, only one of which was the decline of atmospheric CO2. Thus the headline, that “genocide” “caused” the Little Ice Age, seems completely overstated, in the usual journalistic fashion.


I reviewed Chris Given-Wilson’s contribution to the English Monarchs series, Henry IV, for the Journal of British Studies. I am impressed to learn that he is branching out into… Incan history. From Aeon:

Instead of writing, the Inkas’ principal bureaucratic tool was the khipu. A khipu consists of a number of strings or cords, either cotton or wool, systematically punctuated with knots, hanging from a master cord or length of wood; pendant cords might also have subsidiary cords. The basis of khipuaccounting practice was the decimal system, achieved by tying knots with between one and nine loops to represent single numerals, then adding elaborations to designate 10s, 100s or 1,000s. By varying the length, width, colour and number of the pendant cords, and tying knots of differing size and type to differentiate data, the Inkas turned the khipu into a remarkably versatile device for recording, checking and preserving information.

The main uses to which khipus were put were, firstly, to record births, deaths and movements of people, thereby providing an annual census upon which local labour, military and redistributive assessments could be made. They were also used to count commodities, especially the tribute payable by conquered provinces such as maize, llamas and cloth (there was no coinage). Maize, for example, might be represented by a yellow cord, llamas by a white cord, and so on. Early Spanish chroniclers and administrators were astonished at the accuracy of khipu calculations: according to Pedro de Cieza de León, writing in the late 1540s, they were ‘so exact that not even a pair of sandals was missing’.

Read the whole thing.

Gerald of Wales

Enjoyed a good discussion on Gerald of Wales’s History and Topography of Ireland in HIS 323 this past week. Geraldus Cambrensis (c. 1146-c. 1223) was born in Pembrokeshire, Wales, studied at Gloucester and Paris, was ordained a priest, acted as an agent of the archbishop of Canterbury in Wales, and then became a royal chaplain to King Henry II. In 1185, Gerald was chosen to accompany Henry’s son John, who had been named Lord of Ireland, on his first expedition there. The Topographia Hibernica was the result. His descriptions of natural phenomena, and especially his credulity about marvels and freaks of nature, remind me of Herodotus, but this book has a specific agenda – essentially, to justify Henry’s claim to Ireland. He specifically mentions the claim in 92, referencing Geoffrey of Monmouth’s History of the Kings of Britain:

As the British history relates, the king of the Britons, Gurguintius, son of the noble Belinus and grandson of the famous Brennius, when returning from Denmark, which his father had formerly conquered, and which, when it had rebelled, he himself had again brought into subjection, found at the Orkney Islands a fleet which had brought Basclenses there from Spain, Their leaders approached the king, and told him whence they had come and the reason for their coming, namely to settle in a country of the West. They were urgent in their request that he should give them some land to inhabit. Eventually the king, on the advice of his counsellors, gave them that island that is now called Ireland, and which was then either entirely uninhabited or had been settled by him. He also gave them pilots for their expedition from among his own fleet.

From this is is clear that Ireland can with some right be claimed by the kings of Britain, even though the claim be from olden times.

Secondly, the city of Bayonne is on the boundary of Gascony, and belongs to it. It is also the capital of Basclonia, whence the Hibernienses came. And now Gascony and all Aquitaine rejoices in the same rule as Britain.

The kings of Britain have also a newly established double claim. On the one hand the spontaneous surrender and protestation of fealty of the Irish chiefs – for everyone is allowed to renounce his right; and on the other, the favour and confirmation of the claim by the Pope.

For when Jupiter started thundering in the confines of the western ocean, the petty Western kings were frightened by the thunder and averted the stroke of the thunderbolt by sheltering from it in a peace.

Do you find this convincing? The double claim from olden times seems a bit of a stretch. It is true that many Irish kings submitted to Henry, and Pope Alexander III confirmed Henry’s position as Lord of Ireland. (As mentioned elsewhere on this blog, it would have been great if Henry II had properly followed up on this grant and exercised good lordship over Ireland – for starters, not outsourced it to the feckless John.)

The rest of the work follows the usual imperialist script of praise for the land coupled with the disparagement of the people who live there. For instance, “The land is fruitful and rich in its fertile soil and plentiful harvests. Crops abound in the field, flocks in the mountains, and wild animals in the woods” (2). The country “is well supplied with beautiful lakes, full of fish and very large” (4). And not only are there no venomous snakes in Ireland, there are no poisons at all! The land is so pure that poisonous reptiles brought to Ireland die instantly, and Irish boot thongs can be employed elsewhere as antidotes to poison (21-22, 24). The climate is the most temperate of all countries, and there is little need for doctors, given how healthy the air is (26). 

But the people! Some of them are good. There are a few saints, who perform miracles (61-62, 64-65, 68). The clergy are in many points praiseworthy (and should have more power than monks) (104, 106). They are excellent musicians (94), and can throw projectiles accurately (93). But one woman of Limerick had a beard and a mane down her back (53), and a man of Wicklow looked like a man, but had the extremities of an ox, i.e. hooves for hands and feet, and two holes directly on his face where his nose should be. He was likely the product of bestiality between a man and a cow, because in Glendalough another man-cow was born of a similar union (54). In Connacht, a woman entrusted with keeping one of the king’s prize goats ended up fornicating with it (56). Indeed, bestiality and incest are particular vices of the Irish. Furthermore:

• they are not carefully nursed after birth
• their clothes are made in a barbarous fashion
• they do not use saddles or spurs when riding horses
• they go naked and unarmed into battle
• they are a wild, inhospitable people, still mostly pastoralists
• they have no idea about city living
• they don’t realize the potential of their fields for crops
• they don’t mine any of the metals or minerals that abound in Ireland
• they don’t weave flax or wool, and in general do no work at all (93)
• they are ignorant of the rudiments of the faith (98)
• they don’t keep their word, and will physically attack you when they can (99, 101)
• great numbers of them are blind by birth, lame, maimed in body, or suffering some natural defect. This is what you can expect from a people “adulterous, incestuous, unlawfully conceived and born, outside the law, and shamefully abusing nature herself in spiteful and horrible practices” (109).

The only solution, therefore, is to colonize the place, to take advantage of its natural riches and to improve the habits of its benighted inhabitants.

Some of the students in HIS 323 noted the similarity in between this book and the rhetoric surrounding Manifest Destiny in nineteenth-century America, especially the notion that the natives don’t keep their word. I would say that the book not entirely useless as a source – the Irish pastoral lifestyle probably did strike the English as rough and backward, and I would not be surprised if the taboo against bestiality was weaker in Ireland than in England, i.e. it might not have been just something that Gerald made up. The Irish style of horseback riding is confirmed by the Statutes of Kilkenny, and the fact that Gerald is willing to give credit to the Irish for whatever good qualities they have makes his criticism of them somewhat believable.

However, you can tell he’s definitely accentuating the negative. Moreover, the legitimacy of English rule is an entirely separate question. Even if the Irish were as bad as Gerald says, the English could have done much better as rulers of the place than they actually did.

(Quotations from Gerald of Wales, The History and Topography of Ireland, trans. John J. O’Meara [Penguin, 1982])

The End of the Aztecs

From The Independent (hat tip: Tim Furnish):

Mystery over death of 15 million Aztecs may be solved after nearly 500 years, study suggests

DNA analysis of skeletons reveals traces of disease

Judith Vonberg 

Scientists believe they may have discovered the cause of an epidemic that struck Mexico’s Aztec population in 1545, killing up to 15 million people.

In a paper published in Nature Ecology & Evolution, they describe how DNA extracted from the teeth of 29 skeletons buried in a cemetery in southern Mexico revealed previously unidentified traces of the salmonella enterica bacterium.

The bacterium is known to cause enteric fever, of which typhoid is an example. According to the study, the symptoms tally with those mentioned in records from the time, which describe victims developing red spots on the skin, vomiting, and bleeding from various body orifices.

The epidemic was one of several to hit the indigenous population soon after the arrival of Europeans in the early 16th century.

“When the Europeans arrived in Mexico, they brought with them lots of different diseases,” Ashild Vagene, co-author of the study, told The Independent. “There were dozens of epidemics across the New World and Mexico was particularly hard hit.”

“What we’re talking about is the devastating decimation of indigenous populations by previously unknown diseases,” Dr Caroline Dodds Pennock, lecturer in International History at the University of Sheffield, told The Independent.

“Mortality rates were maybe 80 or 90 per cent by 1600,” she said. “Imagine nine out of every 10 people dying – it’s almost unimaginable.”

The cause of the 1545-1550 epidemic has been debated for more than a century. Measles, pneumonic plague and influenza have all been suggested as possibilities, but historians have never reached a consensus.

More at the link.