In the chapter on the rise of Muscovy, Sergey Platonov wrote:
The two first knyazes, Daniil Alexandrovich and his son Yuri, took the lands along the whole river Moscow, tearing the towns Kolomna from the Ryazan principality and Mozhaisk from Smolensk principality. Also, Daniil inherited Pereyaslavl-Zalessky from the childless knyaz of Pereyaslavl. Yuri Daniilovich became so influential that he decided to ask the Golden Horde for yarlyk to become the grand knyaz of Vladimir, competing with the knyaz of Tver Mikhail Yaroslavich (Mikhail was a nephew of Alexander Nevsky and an uncle of Yuri Daniilovich). Since the political struggle in the Horde was led by all means, including conspiracies and violence, both knyazes were murdered in the Horde.
The principality of Vladimir was about 3-3.5 times larger than the duchies of Tver or Moscow. The owner of the title of knyaz of Vladimir became also the grand knyaz, the chief ruler among all the knyazes of the North-Eastern Rus. He defined the joint foreign policy and was the chief military commander in the case of war. Even the free principality of Novgorod recognized the grand knyaz as their supreme ruler. But to become the grand knyaz, one had to obtain the yarlyk from the khan of the Golden Horde. So, since the times of Alexander Nevsky Russian knyazes competed for the yarlyk. In the early 14th century the knyazes of Muscovy and Tver were the strongest candidates.
In 1304 the grand knyaz of Vladimir Andrey Alexandrovich, or Andrey of Gorodets, the third son of Alexander Nevsky, died. His three sons had already died and his heritage produced a huge turmoil among the other knyazes. As a matter of fact, he had bequeathed the principality of Vladimir to his cousin, Mikhail Yaroslavich of Tver. In 1305, Mikhail left to the Horde for the yarlyk.
Yuri Danilovich, knyaz of Muscovy, a grandson of Nevsky, might think he was very unlucky. His father, Daniil, died just one year earlier, 1303. Had Daniil lived a bit longer, the complicated laws of accession would make Yuri Danilovich the grand prince. He was not a legitimate candidate for the princedom, but his principality was stronger than Tver. So, he decided to interfere. As soon as Mikhail of Tver left to the Horde, Yuri followed him. The Moscow boyars and even the Maxim, the metropolitan of Vladimir, insisted that he should stay. He said that he goes to the Horde on his own business, having nothing to do with the yarlyk and departed for good.
When both of them arrived to the Horde, khan Tokhta, a very practical ruler of the Golden Horde, said that the yarlyk will go to the one who offers a larger tribute. Yuri and Mikhail raised the stakes till Yuri gave up. Mikhail stayed in the Horde for some more days, while Yuri hurried back to Moscow. Having arrived there, he immediately sent his army to Pereslavl Zalessky, a town that used to belong to the knyazes of Moscow, but recently adjoined to the domain of the grand knyaz of Vladimir. The excuse used by Yuri was that the deceased knyaz of Pereslavl was an old ally of Moscow. Legally, though, it was a treason and the army of Tver moved to Pereslavl. Mikhail, though, was still absent and Yuri defeated the Tverians. As a matter of fact, the Mongols had to interfere and restore the law. But they were not interested in the rise of one strong grand prince, so they left the two to solve their problems. Besides, who knows who of the princes might offer more money? Having returned to Tver, Mikhail attacked Moscow and forced Yuri to abandon Pereslavl.
But the competition was not over yet. Yuri's brothers, Alexander and Boris, refused to support him, but he still conflicted with Tver time to time, raided his neighbors and his rather aggressive policy increased the strength of Muscovy. In 1306 he killed the knyaz of Ryazan Konstantin, but failed to adjoin Ryazan and had to suffice with Kolomna. In 1307, Yuri attacked Nizhny Novgorod, conflicting with Mikhail once again. In 1308 Nizhny Novgorod Mikhail became the prince of Nizhny Novgorod, but Yuri did not give up. He found a good ally for himself – the new metropolitan of Russia, Peter. In 1312, when khan Tokhta died and khan Uzbek became the new khan of the Golden Horde, Mikhail of Tver went to the Horde to pledge allegiance to the new khan, and Yuri attacked Nizhny Novgorod, where the situation was very similar to what had happened in Pereslavl in 1305. Mikhail wanted to send his army, but the metropolitan Peter intefered and banned him from attacking Yuri.
Uzbek, rather annoyed by that little restless pain in the neck, demanded that Yuri visit him immediately. So, in 1315, the two swapped their places: Mikhail came back from the Horde, and Yuri came there to talk to Uzbek khan. Mikhail took back Nizhny Novgorod and was pretty sure that he could sleep well, even though the Novgorodians didn't like him and revolted now and then. But Yuri did not waste the time. He made acquaintance with Konchaka, the daughter of Uzbek khan and very soon married her. It was a great move. In 1317, Yuri came back to Rus with a large Mongol regiment, led by Kavgadiy, with Konchaka, who was baptised and got the name Agafya, and with the yarlyk of the grand knyaz!
Mikhail immediately made peace with Nizhny Novgorod and went with his army to meet Yuri. They met near Kostroma. Long and tiresome negotiations followed. It seems that Mikhail Yaroslavich agreed to give up his claims. He understood that Yuri will never leave him alone and upon his return to Tver he began to enforce the city and to train the army. The conflict ensued and in December 1317 Yuri attacked Tver but was defeated and fled to Novgorod (not Nizhny Novgorod, but Great Novgorod). Konchaka-Agafya, Yuri's brother Boris, many knyazes and even Kavgadiy were captured. Kavgadiy, though, was soon released with many gifts. Yuri gathered a new army in Novgorod and Pskov and returned to Tver, but this time there were no battles. The knyazes met and agreed to ask the Mongols to end their strife.
In theory, Mikhail had good chances to win. He was richer, he had good contacts in the Horde and he had better support in Russia. Right after the truce, he sent his son Konstantin to the Horde to make arrangements for the dispute.
Suddenly, still imprisoned Konchaka died. Yuri accused Mikhail of poisoning her and left to the Horde. Mikhail didn't plan to follow him, but soon a messenger from Uzbek khan arrived, demanding that Mikhail go with him. By the time Mikhail came to Uzbek, the khan had already learned from Yuri and Kavgadiy a lot about the "evil" deeds of the knyaz of Tver. The slander worked and Mikhail was put on trial. Kavgadiy was both the prosecutor and the judge. On 27 October Mikhail was put in chains and on the next day he was chained to a heavy log. After the trial that took place on 20 November, though, Kavgadiy promised him that he would be released soon. On 22 November 1318, 690 years ago, Kavgadiy, Yuri and a large group of their people assaulted Mikhail in his tent. They threw him down and started kicking him. Then someone Romanets fished out his knife and stabbed Mikhail in his heart.
His body was sent to Tver and on 6 September 1319 a huge crowd of people attended his funeral in the Tver cathedral. They were so frightened by his death that soon they forgot Mikhail's feuds with other knyazes, the ransack of the civilians in Torzhok in 1316, forgot how he had brought the Mongols and so on. They even began worshipping him as a saint.
In 1319-1320 this story was written by hegumen Alexander, Mikhail's father-confessor.
On 21 November 1325, almost exactly 7 years after the death of Mikhail, Yuri of Moscow was killed in the Golden Horde by Dimitri Mikhailovich, knyaz of Tver, son of Mikhail of Tver. Dimitri was also killed on spot.
To make the story just a little bit easier to read, here's the family tree of Rurikids, the Russian knyazes: