Extreme Weather

"Volcanic winter" is a frightening phrase. It is the result of a volcanic eruption that spews so much ash and dust into the atmosphere that it encircles the globe and prevents sunlight from reaching the surface of the Earth. 

A volcanic winter took place in the 530s CE, the most severe drop in temperature in the Common Era. An eruption of sulfate aerosols possibly in late 535 dropped summer temperature averages in 536 by at least 4-5 degrees Fahrenheit. In 539-540, a second volcanic eruption caused summer temperatures to drop another 5 degrees.

This was recorded in the Northern Hemisphere by contemporary writers in Constantinople. Procopius, whose writing revealed the secret of where silk came from, records of 536 

...during this year a most dread portent took place. For the sun gave forth its light without brightness … and it seemed exceedingly like the sun in eclipse, for the beams it shed were not clear."

Cassiodorus, in a letter in 538, describes the sun's rays being weak, no shadows from people at noon, the sun's heat being feeble, the moon "empty of splendor," prolonged frost, unseasonable drought, frosts during harvest, the need to use stored food because harvests were so poor.

The Annals of Ulster mention a failure of bread in the year 536.

Dendrochronology (tree ring analysis) shows very poor growth in Irish oak in 536. Ice cores from Greenland and Antarctica show substantial sulfate deposits around 534±2 years, which offers evidence for the volcanic eruption. Which volcano was the cause, however, has never been agreed upon. The 536 event was worse than 1816, when the explosion of the Mount Tambora volcano caused the "Year Without a Summer."

As mentioned in the prior post, the line regarding the Battle of Camlann in the Welsh Annals that says of 537 "there was great mortality in Britain and Ireland" is likely a reference to the famine that resulted from the volcanic winter.

The 536 event was not the only severe weather crisis in the Middle Ages. Next time, let's jump forward to the Great Famine of 1315-17.

500

This is the 500th post on the Daily Medieval blog. In its honor, let us look at the year 500 CE and how it overlaps some of the previous 499  posts.

500 was a leap year. January 1st was a Saturday. July 4th was a Tuesday.

It was the birth year of Gildas, a monk, who wrote the De Excidio et Conquestu Britanniae ["On the Ruin & Conquest of Britain"], a chief source of history for early Britain, although much is called into question. A life of St. Gildas written later by a friend of Geoffrey of Monmouth makes Gildas out to be a contemporary of King Arthur, and yet Gildas never mentions him. He does mention the Battle of Mount Badon, for which 500 is a possible date.

It is the year that Clovis I pursues King Gundobad of the Burgundians after a military engagement, forcing him to pay annual tribute.

It is the approximate date of the formation of the Kingdom of the Franks, that reached a high point a few centuries later with the family of Charles Martel.

It is the approximate birthdate of Aregund, whose jewelry provided an impressive grave excavation.

It is the birthdate of the Byzantine historian Procopius, from whom we learn how the West got the secret of silk from Nestorian monks.

500 was, of course, only the year according to the Julian calendar.
For the Romans, it was 1253 Abs urbis condita ["from the city's founding"].
Jews considered it the year 4260-61.
The Byzantines numbered years from the founding of the world, 5509 years before Christ, so to them it was 6008-09 (the year started on 1 September).

Thanks for reading!

Got Silk?

Silk was not a medieval invention. According to Chinese tradition, Empress Si-Ling-Chi in 2460 BCE watched silkworms spinning cocoons; she unwound several cocoons, then ran the strands together to make thread, then wove the result into cloth to make a robe for Emperor Huang-Ti.

The Silk Road routes

Unverifiable, but it may very well be true. What is slightly more historically documented is that China guarded the secret of this magnificent fabric for centuries, but was willing to manufacture the cloth and sell it for very high prices to others. Wealthy people from other countries would gladly pay large sums to purchase it—soft and smooth, light to wear, dyed easily—so knowledge of this material spread. India somehow figured out the secret and was manufacturing its own silk by the 2nd century CE.

Ezekiel mentions silk, which means it was known to the Middle East in the 6th century BCE. Aristotle mentions the process of dealing with the cocoons, but the knowledge must have been lost for awhile, because it seems to be a mystery to that part of the world centuries later. We are told that Julius Caesar (100-15 March 44 BCE) had silk curtains. It is thought that the Romans first encountered silk in the hands of the Parthians in the first century BCE. By the end of the 1st century CE, Rome was trading for silk with the Parthians; we don't know what kind of "mark up" the Parthians were putting on the silk that they got from the East, but it was probably substantial. Although more than silk was traded between the East and West, silk was one of the few things only available from the Far East, and so the collection of interconnected trade routes from China and India to Byzantium and Alexandria became known as the "Silk Road."

Of course, it is cheaper to manage production yourself, and the Byzantine scholar Procopius (500-565 CE) tells us how some Nestorian monks* gave the Emperor Justinian the secret: the thread comes from silkworms that could not survive transportation, but their cocoons would travel well if insulated in dung and fed on mulberry leaves when hatched. Byzantium created a thriving silk industry and supplied Europe for centuries. The silk factories were staffed by all-female crews, and so were called gynaecea—after the name given to the section of a Roman or Greek home devoted to women.

Marco Polo on the Silk Road

The cycle of industrial espionage continued, however, when Muslims, who learned the secret of silk when they conquered Persia, took over Sicily and Spain. By the 13th century, Europe was producing its own silk and purchasing less from Byzantium. By the 15th century, France had its own factories. This was necessary, according to Louis XI, because purchasing silk from Italy created a trade deficit for France of 40-50,000,000 gold écus.**

Silk is different from cotton or wool in that it is not spun; rather, two or more strands are twisted together. To produce this, new techniques were invented. The simple reel is said to have been first devised for holding strands of silk, which could be up to a mile long. Two reels would be set up to unwind simultaneously so that their strands could be twisted together in a technique called "throwing."

The Middle Ages loved silk so much that a whole new vocabulary was created to describe its uses in fabrics:

• alexander - a striped silk
• baldachin - a warp of gold thread with a woof of silk
• begin - 14th century rayed silk fabric
• camlet - half silk/half hair (such as angora)
• cendal - woven silk material
• ecarlate - high-quality silk
• gauze - semi-transparent silk (from 13th century onward)
• imperial - silk with gold thread; originally from Byzantium, later called baldachin
• osterni - silk dyed purple
• samite - silk with interwoven gold or silver threads
• sarcenet - thin soft silk with slight sheen; sometimes called "shot"
• tartaire - silk from Tartary

...and in all these centuries, it hasn't lost its luster.

*Remember the Nestorians? They were a branch of Christianity deemed heretical a century before Procopius, who made their home in the East where William Rubruck ran into them.
**Story of the Silk Road by Yiping Zhang, p.146 (I don't normally bog things down with citations—I assume you trust me!—but this number was so ... impressive that I felt the need to point to a source. It may be a huge exaggeration.