Help! I searched this up on Google and there was nothing, I even looked it up on the Wikipedia. I need information by tomorrow. It is for a project.
There are quite a few sources out there, both old and recent, from which we can narrow just how far a Mongol Horse could travel in a day. We can start with some basic information.
The walk is a four-beat gait that averages about 4 miles per hour (6.4 km/h).
So at this rate, an average horse could cover as much as 32 miles (51km) in a solid 8 hr day long walk. I would use this we can take as a minimum estimate.
Another gait discussed is a trot:
The trot is the working gait for a horse. Despite what one sees in movies, horses can only canter and gallop for short periods at a time, after which they need time to rest and recover. Horses in good condition can maintain a working trot for hours. The trot is the main way horses travel quickly from one place to the next.
The above article also mentions the trot has an average speed of 8 mph(13 kmh), which over an 8+ hour day might give us a distance of over 60 miles (97 km). But this is general information, so lets look for some specifics to the historical aspect of the question.
We have some historical sources concerning the Mongols, the primary one being Marco Polo. We can refer to his original information when referring to the Mongol messenger system, known as the Yam. From The book of Ser Marco Polo, the Venetian: concerning the kingdoms and marvels of the East
pg 420 province leads and it is a very sensible plan 1 And the messengers of the Emperor in travelling from Cambaluc be the road whichsoever they will find at every 25 miles of the journey a station which they call Yamd or as we should say the Horse Post House And at each of those stations used by the messengers there is a large and handsome building for them to put up at in which they find all the rooms furnished with fine beds and all other necessary articles in rich silk and where they are provided with everything they can want If even a king were to arrive at one of these he would find himself well lodged At some of these stations moreover there shall be posted some 400 horses standing ready for the use of the messengers at others there shall be 200 according to the requirements and to what the Emperor has established in each case At every 25 miles as I said or anyhow at every 30 miles you find one of these stations on all the principal highways leading to the different provincial governments and the same is the case throughout all the chief provinces subject to the Great Kaan Even when the messengers have to pass through a roadless tract where neither house nor hostel exists still there the station houses have been established just the same excepting that the intervals are somewhat greater and the day's journey is fixed at 35 to 45 miles instead of 25 to 30 But they are provided with horses and all the other necessaries just like those we have described so that the Emperor's messengers come they from what region they may find everything ready for them...
So the Yam established stations to change horses for the messengers and were positioned anywhere from 25 to 30 miles apart in more developed region, to 35 to 45 miles apart in less developed regions. Then Polo describes the distance a messenger on this system might be expected to travel (also from Polo):
pg 421-422 pays Moreover there are also at those stations other men equipt similarly with girdles hung with bells who are employed for expresses when there is a call for great haste in sending despatches to any governor of a province or to give news when any Baron has revolted or in other such emergencies and these men travel a good 200 or 250 miles in the day and as much in the night I ll tell you how it stands They take a horse from those at the station which are standing ready saddled all fresh and in wind and mount and go at full speed as hard as they can ride in fact And when those at the next post hear the bells they get ready another horse and a man equipt in the same way and he takes over the letter or whatever it be and is full speed to the third station where again a fresh horse is found all ready and so the despatch speeds along from post to post always at full gallop with regular change horses And the speed at which they go is marvellous.
So here we can find what may be a maximum rate of travel for a rider in special circumstances. I stress for the rider, because we know they were switching horses at these stations. We can, however, estimate a maximum rate for the Mongol horse assuming these numbers represent riding as fast as they could go. 200-250 miles (321-402 km), over our 8 hrs, gives us speeds of 25-32 mph (40-51 kmh), over the minimum listed distance of 200 miles. This would be absolute max, a top limit, since these horses only were used for short sprints and then could rest and eat.
I know we mentioned the switching of horses at these Yam stations, so what relevence does this information have, since it represents travel using multiple horses? I list it because that is exactly how the Mongol warriors traveled, each having several well-trained horses at their disposal:
A Mongol warrior's horse would come at his whistle and follow him around, dog-like. Each warrior would bring a small herd of horses with him (three to five being average, but up to 20) as remounts. They alternated horses so that they always rode a fresh horse
So now we know what a Mongol horse could achieve 'full-out', and we know several changes of horse would be available, so each horse might only be expected to bear a rider at high speeds for a portion of a day. But we don't know how long a typical day might have been, how long the rest periods might have been when the armies slowed to a walk or a canter. We can look for some historical information again to help us understand just how far the Mongol armies might have actually traveled.
A fairly recent book(2015),Genghis Khan and the Mongol War Machine By Chris Peers , gives us the following information: pg 69
Martin quotes Douglas Carruthers as saying that in the early twentieth century a Mongol riding a single pony would routinely travel 600 miles in nine days, and calculates that on a two-day march from Bamiyan to Ghazna in 1221 Genghis' army covered 130 miles.
Another source,The Horse in the Ancient World, by Ann Hyland (with a limited view however) seems to agree with the above figures on pg 37:
In the depths of the winter of AD 1241 Mongol armies moved through the Carpathian Mountains in the invasion of Europe covering 60 miles per day
Both of these figures indicate that a Mongol horse could (and did) travel 60-65 miles (96-104 km) in a day. This seems to directly answer the OP's question, To see if this makes sense compared with the other information collected, we can do a couple more calculations. If we call this an 8 hour day, we get around 8 mph, which is twice the walking rate, and half the lower end of the 'flat-out' Yam rate. Seems to fit, and is coincidentally the same number we got concerning the average speed of the trot.
- So, bottom line, I would say a Mongol horse could be expected to travel 60-65 miles (about 100 Km) in a day.
Note: As @PieterGeerkens points out in comments this may have been a special occurrence, essentially a forced march, and the typical average pace may have been less. His answer to another question on feeding these massive herds has good information on the logistics concerning grazing such large herds of horses, well worth a look.