The secret to Genghis Khan's military effectiveness | Jack Weatherford and Lex Fridman

And so there's light cavalry and heavy cavalry, and breaking down units, using the decimal system — 10, 100, 1,000 — so there's a kind of hierarchy where you delegate authority, but to the degree there's commands, they must be followed strictly.

I think the first point is the extreme loyalty of the people whom Genghis Khan chose. His kinsman, as we said, had deserted him; his anda was a questionable relationship, but all the others that he found were just common people — herders or hunters, very common — and they were loyal to him, and never ever revolted against him, never betrayed him. So he had extreme loyalty. And then, as you mention, he organized his decimal system, so the smallest unit of the army was the aravt, the 10, the squad of 10 men. They were put together, and then the head of that squad, he had total control over it, but the men knew that they were going to protect each other, and they had to come back with every member, or everybody — you don't leave anybody behind. So this was extremely important. So if you submit to the orders of the man in the aravt, you know that he's risking his own life for you also. And you know that your brother on the left and on the right is risking his life for you.

The army was — they organized it with five horses. Each man, they had their bow, and they had a lot of arrows, as many as they could have, but they also retrieved arrows at the end of their battle, and they also would retrieve the enemy arrows. This was a great advantage, by the way, where they hit Russia, because the Russians could not use Mongolian arrows — they could knock them in their bow — but the Mongols could use Russian arrows. But so all these little things, but it's not even just the arrow, and also they had to carry needle and thread. Every soldier had to be able to sew. And sometimes that could be a torn garment, it could be a piece of skin, or a wound that somebody has. It was a very odd thing when you think about the army of Genghis Khan, and they're carrying everything themselves, they don't have any pack train behind them, and that one of the things they have to carry is needle and thread, in order to sew up things.