Why did the Mongols easily reach Russia? Before answering this question, let's take a look at the route from Beijing to San Francisco. Fly from Beijing through the northeast, then through Russia's Kamchatka Peninsula, over the Aleutian Islands, and finally land in San Francisco.
Let's look at the flight from Beijing to the East, such as Washington, New York and other places, all over the Arctic. Looks like a big detour, is there? So the question is, why not fly in a straight line across the Pacific Ocean?
This is the misunderstanding that the Mercator projection map has caused us. The Mercator projection treats the Earth as a cylinder and then unfolds it into a map, which causes the higher the latitudes to be stretched. If you take out a globe, you know that the shortest distance is the northern "curve", and the so-called "flying a straight line across the Pacific Ocean" is actually a more detour. Having studied spherical geometry, this question is not difficult to understand.
For example, when we look at Greenland on the map, it seems to be about the same size as Africa, because the high latitudes have been enlarged. In fact, Africa is 13 times the size of Greenland, which is not the same size at all.
Genghis Khan led a large Mongol army from the Hangai Mountains of Mongolia to the west, all the way to the southern Russian steppe, which we look at from the flat map as a long distance. This is also a misunderstanding caused by the Mercator projection map, in fact, from the Hangai Mountains to the Volga River in Russia, it is only about 3900 kilometers. What is the concept of 3900 kilometers, from Shanghai to Urumqi there are 3300 kilometers. Therefore, the Mongol army fought from the Hangai Mountains to the Volga River, and the distance was really not too far.
Mount Hangai in Mongolia was called Yanran Mountain in ancient China. In that year, Dou Xian of the Eastern Han Dynasty broke the Northern Xiongnu and fought all the way here. Ban Gu, a historian who accompanied the army, carved the "Feng Yanran Mountain Inscription" on the stone wall of Yanran Mountain.
The Mongol army set off from the Hangai Mountains through the Altay region to the those Stan countries in Central Asia, which was basically a horse on the Pingchuan steppe, which was very suitable for Mongolian iron horses to run horses. When Genghis Khan was in the Jade Dragon Jechi (Urgenchi of Uzbekistan), he asked Tebetsu and Subutai to lead the army to continue the western expedition. As a result, he did not take a few steps to kill the Volga River, and from then on began the story with Russia...
The Mongols could easily reach Russia, and in addition to their own combat effectiveness, the objective conditions were also favorable. The first road is not too far away, and the second road is also easier to walk, which is very suitable for cavalry combat. If the Mongols originated in the Central Plains, I am afraid that the history will be different, and the journey from the Central Plains to the Western Regions alone will be very difficult to walk, requiring a lot of time and grain. In that year, Emperor Wu of han sent Li Guangli on an expedition against the Xiongnu, which directly caused the state finances to be empty and the people to be bored, so they had to issue the "Wheel Of Taiwan Edict" and repent of their mistakes.