“Before leaving, he ordered the execution of the chiefs, following the traditions of ancient China. Seventy cauldrons were prepared for the execution.”
As you already know, Genghis Khan found his first wife when he was still a child, the little ones were matched by their parents. The agreement was so strong that Borte’s father did not give up on it even after the death of Yesugei (Genghis Khan’s father).
And though single mother Oelun (Genghis Khan’s mother) was abandoned by her husband’s tribe, wandered with her children on the steppe without shelter and struggled every day not to starve to death, Borte was given to Genghis Khan when she reached the age of marriage, despite the plight of the groom.
Genghis Khan grew up, absorbed with his mother’s milk the idea that he would become a great khan, would restore his status and would definitely surpass Yesugei, and he was not going to retreat. Gradually Temuchzhin (Chinsgis Khan’s real name) began to gain momentum.
His twin Jamukha was a strong warrior, they tried to preserve their childhood friendship, but when it comes to power, many things are forgotten. Jamukha went to war against Genghis Khan, and although he won the first battle, it was Genghis Khan who emerged from this conflict as the true victor.
How did he do it? Who and for what boiled the prisoners in seventy cauldrons, I will tell you now.

“As always, the third extra is guilty.”
Jamukha and Temujin tried to maintain correct relations, and though they both realized that this would become impossible after a while because of the rapid political development of the warriors, they tried to prolong the age of friendship as long as possible.
Jamukha is an old faithful friend of Genghis Khan, the one who helped the great warrior to return his wife Borte, the one who was not afraid to go against the warlike Merkits. But any friendship comes to an end when a third extra enters it. That’s what happened between Jamukh and Temuchzhin.
One day Jamukha’s younger brother Taichar decided to take advantage of someone else’s herd and stole the horses of Dzhuchi-Darmal (Genghis Khan’s vassal). Dzhuchi could not sit idle for long:
“To steal right from under his nose — what rudeness!”
Juchi went to take revenge, no one dared to support him, Jamukh’s army was powerful and the Mongols did not want to take risks because of horses.
He quietly crept up to the camp of the enemy, tracked down Taichar and struck a blow — an arrow hit the thief’s back, and he fell with a broken spine.
Juchi-Darmala proudly took the stolen horses and returned home. This was the beginning of the war.
“A battle won/lost.”
Blood revenge is the most powerful revenge.
After losing his own brother, Jamukha gathered his army and set out to avenge his twin (twinning is a rite of passage to cement friendship and equate it with brotherly relations).
The army, which Jamukha managed to gather, amounted to 30 thousand people, Genghis Khan was far behind, in his camp at that time there were 30 thousand people in total, including women and children, the warriors themselves were much less.

Jamukha (in the cinematic universe)
It was decided to attack unexpectedly, fortunately for Genghis Khan, he received insider information and had time to prepare for the battle. The two “brothers” met at the “Seventy Swamps”, somewhere at the source of the Onon. It was a terrible battle, which brought both sides a lot of losses, Genghis Khan lost it and was saved by a timely retreat.
Jamukha was afraid to pursue Genghis Khan and decided to finish his revenge by executing the captured leaders.
An incredible torture and a terrible death awaited Genghis Khan’s supporters. Jamukha ordered to boil them in seventy cauldrons, such execution was used in ancient China. And a separate fate was prepared for the Chonos chief Chahaan-uva: his head was cut off and tied to a horse’s tail and taken away with him.
“The Rise of Genghis Khan.”
Despite losing this terrible battle, Genghis Khan rose in the eyes of other tribes, and the attitude to the fierce Jamukha extremely spoiled.
Genghis Khan found new allies and brought back old friends. To the great Khan joined Chzhurchedei from the Uruut tribe and Khoildar from the Manchuud tribe, they would play an important role in the victories of Genghis.
“The Return of the Prodigal Traitor Father Genghis Khan.”
But most interestingly, Genghis Khan’s army was joined by a certain Munlik. It was an old faithful friend of Genghis Khan’s father, whom Yesugai ordered after his death to become the guardian of his children. However, Munlik neglected the role of guardian, and together with the tribe banished poor Oelun, left her alone to bring up her children, and chastised her for hunger and loneliness.

Genghis Khan
Genghis Khan forgave the traitor, who not only refused his father’s commission, but for some time fought on the side of Jamukha.
Although Genghis Khan lost this battle, it gave him a chance to rise. Tribes began to reach out to him, and he received each of them with honor, thus gradually building up a huge and strong army.