[aruanan]

All you need to understand how a bunch of un-educated guys dressed in last year's rags were able to move out of Arabia and conquer Damascus is note that even Byzantium hadn't paid its troops in over a century when the legions met the guys from Mecca.

The early Moslems did most of the conquering with Byzantine armies and Byzantine navies ~ who they paid!

The Bedouins of the Arabian Peninsula had long served as mercenaries for both Rome and Persia in their internecine conflict. It was the advent of a plague originating in Africa that weakened both Rome and Persia to the extent that they didn't need/couldn't afford these mercenaries who, organized by Mohammed under the banner of Islam, took advantage of the weakened North African/Mediterranean world and swept through it like a plague, concentrating not on rule but on plunder (look at the letter back to Caliph Omar at central command, so to speak, listing all the houses and other stuff to be had in Alexandria: "I have captured a city from the description of which I shall refrain. Suffice it to say that I have seized therein 4000 villas with 4000 baths, 40,000 poll-tax paying Jews and four hundred places of entertainment for the royalty"), not too distant from when Muawiyah, your namesake, the first Arab governor of Palestine, was made the first Omayyad Caliph of Damascus.

[muawiyah]

There were always plagues, but the world economy had been in freefall since 541 AD. The Plague of Justinian started about then, of course, but the volcanos did their job in 535 AD and destroyed the Northern and Western European economies. The civilizations around the Mediterranean began suffering and finally their economies faltered.

For a variety of reasons the people working the caravans from Petra to Mecca to Medina had remained relatively isolated from these other devastating events, or, most likely, they were affected equally but didn't realize it due to their normally deep level of poverty and their physical isolation from the Mediterranean world.

There are interesting debates regarding the degree of European depopulation. First of all no one doubts that millions died from the plague and whatever the weather anomaly was that gave Western and Northern Europeans an incentive to burn almost every piece of furniture, parchment or other burnable in a short period from 535 to 541. Secondly, back in the days before unemployment insurance, modern machinery, food surpluses, trucks, trains, cars etc. it didn't take much of a disaster for darned near everybody near it to die if only from simple starvation.

Thirdly, there are "secondary diseases" that take the opportunity to kill under these conditions.

Whatever, the death rates were different in different places. The Eastern Empire lost just under half its people. The Western Empire probably lost over half along the Mediterranean and more like 90% in the NW.

The Arabs in the peninsula didn't know anything of this.

BTW, the invasion of the Mediterranean civilization didn't begin until AFTER Mohammad was dead and AFTER Petra was converted. You should note the name of that place ~ it's in Jordan. They appear to have gone cash at the beginning of the disaster and could pay hard money for whatever the Moslem commanders needed.

If the Arabs had been Roman Catholic Monks the outcome would have been the same!