At various points in preceding chapters the reader will have noticed references to AD 540 and climatic events in the sixth century. The sixth century is undoubtedly a Dark Age when we know relatively little of what was happening in the world. What little we do know tells us that the world seems to have been experiencing extraordinary change.1 From the perspective of Irish records, we know that there is almost no contemporary documentation; everything about the earlier sixth century was written down later. In Britain it is widely held that there was only one contemporary writer, Gildas, who traditionally was believed to have been writing around 540. His writings are essentially apocalyptic in character, and he draws heavily on Old Testament descriptions to illustrate points – almost all of them bad news. In Britain, in 537, there was the mythical battle of Camlann, in which Arthur and Medraut fell ‘and there was mortalitas in Britain and Ireland’.2 Ten years later, in 547, there was another great plague in which Maelgwn, King of Gwynedd died; this is normally called the ‘yellow plague.
In Ireland, the Annals of Ulster record a famine or ‘failure of bread’ in 536 and again in,538, along with a battle of Luachair. In 544, the first mortality called Bléfed arrives, killing St Mobhi, and presumably many others besides. In the Annals of the Kingdom of Ireland this is given as 543, with: ‘There was an extraordinary universal plague through the world, which swept away the noblest third part of the human race.’ In 553, there is a pestilence, perhaps leprosy, called the sámthrose. In 555, there is a great mortality due to the Battle of Chonail or Chrom Chonaill that has been suggested to be yellow fever. So, given how thin the records are back in the sixth century, the annalists are at pains to point out a variety of severe plagues within about a decade in the middle of the century.
Archaeology has revealed that certain settlements such as Lough Shinney in Dublin and Garranes in Cork came to an end in the mid-sixth century.3 In the midst of all this chaos, the last feasts of Temair (Tara) were held before its abandonment in the 6os. Indeed, ritual and religion become increasingly important. As we’ll see in Chapter 19, many monasteries were founded around this unsettled time. These general signs of stress were not confined to Britain and Ireland. The plague associated with Justinian is first mentioned in 540. It seems to have arrived in Egypt in 541 and Constantinople in 542. It is estimated to have killed more than one third of the population of the Roman Empire, very much in line with the comment in the Irish annals. The plague is reputed to have caused demographic, economic and political chaos. For example, in southern France, its effects helped to ensure the rise to power of the Franks based in the north. So it goes on; the mid-sixth century seems to have been ‘interesting’ for those who lived through it in Europe.
Climatic disruption also caused chaos in Asia. Faced with drought, the horse-based economy of the Avars in Mongolia apparently lost out to the cattle-based economy of the Turks, causing the Avars to lose power to the Turks in AD 545. This forced them to move west where they, in turn, uprooted the Slays and Lombards, severely weakening the remnants of the Roman Empire.4
In North China, there was a severe drought in April 535, causing many deaths. In September 536, there were falls of hail and a great famine. By December, famished refugees were roaming around north of the Yellow River. It is reported that during the ‘great famine’, at least at local level, ‘the people practiced cannibalism and 70-80 per cent of the population died’. Meanwhile, in South China, there were reports of yellow dust raining down like snow in November AD 535, or dust that could be ‘scooped up in handfuls’ in December 536, and rain that was ‘yellow in colour’ in February 537. These events were followed by very unusual frost in July of 537, and even snow in August. This, in turn, caused crop failures that led to widespread famine. Things were apparently so bad that there was a tax and rent amnesty in September 538. Drought in early 538 was followed by a massive flood that summer, and this general sense of climatic dislocation extends into the 540s with more droughts in 544, 548 and 549, severe famines, and reported cannibalism in 549 and 550.The 538 tax amnesty was repeated in 541 and extended until Indeed, things were so bad that the country split in two, smaller political units being more easily managed in a time of crisis; China was not reunified until 588.5
Similar effects are seen almost everywhere that records exist. In North India, Yashodharman’s empire disappeared with his death in 540. India then broke up into a cluster of small kingdoms. In Korea, in 535 to 536, flooding was followed by a great epidemic, followed in turn by a severe drought. In Japan, where everything had been wonderful in 535, there was a sudden crisis so that in 536, people were suffering from appalling hunger. The Japanese Nihonshoki chronicles the words of King Senka:
Food is the basis of the empire. Yellow gold and ten thousand strings of cash cannot cure hunger. What avails a thousand boxes of pearls to him who is starving of cold?
There was a large flow of immigrants to Japan, probably from Korea. Meanwhile, in the Americas, the city of Teotihuacán, Mexico, home to I25,OOO-200,000 inhabitants, was abandoned in the sixth century. So too was the religious centre of Cahuachi in Peru. The Moche State in Peru became destabilised by droughts and floods.6
RELIGIOUS CONSEQUENCES
This sixth-century episode of chaos seems to have had a clear religious dimension. In Spain, it converted the ruling elite from Arianism to Catholicism. In China, the southern Emperor personally ploughed the ritual first furrow in March of all but one of the years 534-541.There was a rise in the belief in the ‘Left Way’ of Buddha. Conventional Buddhism believes that the Buddha will return one day as the Maitreya to save the world, though this is not expected for millennia. In the Left Way, the Buddha’s arrival was expected much sooner. Something around 540 led people to believe that the Buddha’s arrival was imminent. This rise in belief in the Left Way resulted in a revolt in Ancheng in 542.
In Korea there was an official conversion to Buddhism by the government of Silla. In 536, the king announced the beginning of a new era: the Konwon. Then, in 538, the King of Paekche in Korea sent a Buddhist religious mission to Japan with a statue and books. The Great King of Japan decided to experiment, allowing the head of the Soga clan to worship Buddha. He built a temple to Buddha. But when an epidemic broke out, killing approximately 60 per cent of the population, the king’s decision was blamed. The statue was thrown into the canal, the temple was burnt and the king was assassinated. The row over Buddhism continued throughout the sixth century until the religion was finally adopted in the 590s.
In the Americas, inTeotihuacán, religious buildings became a target of hatred, with around 50-60 per cent of temples torched by an angry mob. When the city of Calakmul, led by King Sky Eye attacked the rival city of Tikal in 562, they waited until a date when ‘Venus’ was likely to rain down cosmic darts and destruction. After a successful attack, they installed a young puppet king called Great Sun Reptile Head.8 In Peru, the religious centre of Cahuachi was abandoned during the great drought and emphasis switched to the development of desert drawings the Nasca lines. Images on Nasca pottery portrayed more violence, with one deity turning into a demonic monster.9
ENVIRONMENTAL EFFECTS
If we were to go back, say, 20 years, and produce the above compilation, it would have been generally assumed that this was all just an unfortunate clustering of random events. Occurring across the world, what connection could there possibly be between what happens to a city state in Mexico and an outbreak of plague in Ireland or China? What has emerged in recent years, as detailed in Chapter 17, is the idea that all of these events are in fact connected - they are all the results of a global episode of environmental stress.
Dendrochronology has brought this realisation about. From European oaks, through pine chronologies from Sweden, across to Mongolia and from California to Chile, dramatic effects in trees have been observed across the years from 536—545 (67). So there was undoubtedly a global tree-ring downturn effectively centred on AD 540. Given that context, a lot of the otherwise disparate historical references start to take on a new ‘colour’. Similarly other environmental effects, whether they involve ancient rivers in Colombia, or an ice core from Peru’s Quelccaya Glacier, all point to a massive drought in South America between 540 and 570.10
SUGGESTED CAUSES
So what caused this environmental downturn? Well, David Keys, who accumulated much of the global information just given, felt that the sheer scale of the global catastrophe from 536-545 was so profound that, if it had involved an impact from space, the impact would have had to be so colossal that evidence for it could not have been missed by geologists and others. In fact, he proposed that to cause the global environmental effects any ‘impact from space’ would have had to be either with a 2.5-mile diameter asteroid (solid stony or iron object) or a 4-mile diameter comet nucleus.
