The Mongols are a tribe that played an important role in medieval world history and came to the fore with their destruction in the Islamic world. The Mongols only played an essential role in world history in the 13th century, when Chinggis Khan founded the Mongol Empire at the beginning of the century. After long struggles, Chinggis gathered all Mongolian tribes under a single state. Chinggis received the title of khan through the kurultai held in 1206 and became the greatest ruler of all steppe tribes. Afterward, Chinggis Khan took control of the Kyrgyz, Merkit, Naiman, and Uighur until 1209. With the administrative, social, and military regulations he made, Chinggis Khan brought the Mongols under a regular organization for the first time in their history and restructured them with the concept of a world state. With the capture of Qara-Khitai lands, the Mongols became neighbors to the Khwarazmshah in the west. However, these neighborly relations did not continue as normal. In 1218, a Mongol caravan of 450 people was slaughtered in Utrar. Their goods were plundered, and the ambassadors were killed. Afterward in the following year, Chinggis Khan went on an expedition against the Khwarazmshah with a strong army. Instead of fighting a pitched battle against the Mongols, 'Alā’al-Din Muhammad Khwarazmshah preferred to fight a defensive war by dividing his army among the cities. However, this attitude ended the Khwarazmshah and resulted in the towns of the Khorasani geography facing the Mongol invasion. Chinggis Khan also sent his youngest son Tolui to Khorasan. After Tolui captured Merv, Nishapur, and Herat, he joined his father in besieging Taleqan between Balkh and Marw al-Rudh. Chinggis Khan spent the summer of 1220 in Nakhshab and then captured Termez. The following year, he crossed the Oxus River and captured Balkh, and the Mongols invaded all Khorasani cities.

In the Middle Ages, the struggle of states to establish superiority over each other took place in different dimensions. While these were sometimes bloody and destructive, other times they were peaceful. The battle of the Mongols in the Khorasan geography attracts attention for its bloody and violent dimensions. The Mongols’ struggle with the Khwarazmshah, one of the political actors of the period, brought a significant change to Khorasani geography. Once the Mongols took over the entire Khorasan geography, they tried to establish administrative order there through new administrations. Perhaps the Mongols needed to pass the test successfully in the Khorasani geography in order to prove their maturity and emerge as a political and military power.

The Mongol invasion is one of the most talked about events in the Middle Ages. Through this period of invasion that started under the leadership of Chinggis Khan, many residential areas either suffered significant damage or were destroyed entirely. The greatest of these destructions occurred in the Khorasani geography. The Mongols are in fact remembered in world history for their destruction. This situation had emerged due to a strategy the Mongols implemented in the places they captured. What happened in Transoxiana and the Khorasani geography significantly impacted the formation of this image. Of course, sources differ in terms of the extent of this destruction. In addition to those who’ve stated that the destruction was not as great as thought, some approaches show this to have been a natural situation. Among the reasons behind the destruction the Mongols carried out, the first thing one see is that it had been a military strategy. The Mongols used this strategy to devastate the border regions, with the aim being to make an area clear for subsequent conquests. Another reason that came to the fore in the Mongols’ destruction was their sense of revenge. The invasions Chinggis Khan carried out had started with the murder of Mongol ambassadors and reached very different dimensions in the cities where members of the Mongol dynasty had been killed. The Mongols inflicted much greater destruction in the Khorasani cities they’d captured with a passion for revenge. In addition to religious and ethnic elements, other elements such as the strategic locations of the regions, the disobedience of the locals, steppe tactics, nomadic life, and the betrayal of the Khwarazmshah come to the fore as reasons for the destruction. Based on all these approaches, briefly describing what the Mongols did in Khorasan as barbarism may lead to a mistake in explaining what happened in the region. In this respect, evaluating the policy the Mongols followed in the cities of Khorasan would be a more accurate approach due to the strategy they implemented to establish dominance in the region.

The literature has a massive gap in terms of construction after the 1220s in the Khorasani cities that had been exposed to Mongol invasion. The Mongols changed the landscape of every town they went to. After the Utrar incident caused by the Khwarazmshah, Chinggis Khan led the Mongols to take action as revenge for the murder of their ambassadors, or at least used this as an excuse. Thus, the Mongols’ pursuit of 'Alā’al-Din Muhammad Khwarazmshah significantly destroyed the Iranian geography. The cities of Khorasan in Iran received the most significant share of this destruction. Herat, a Khorasani town, had also been destroyed by the Mongol invasion.. Ögedei declared a general amnesty and made many grants. After reorganizing the internal administration, he resumed the reconstruction that had been on hold for a long time. While Chinggis Khan had sent Chormaqan Noyan to Iran in 1231 for the planned Near East expedition, he had marched to China. Through bureaucrats such as Chin Timur and Korguz in Iran, Ögedei Khan organized the internal administration of large regions that had been captured during the war and turned into ruins. Therefore, these administrators initiated development activities in the geography of Khorasan and Herat. 

Of course, the construction activities in Herat were closely related to Ögedei’s attitude on this issue. Ögedei Khan attached importance to development. After a while, the Mongols under Ögedei started construction work in the cities they had captured through destruction and founded new cities. Karakorum was established near old Ordu-Baliq, and water wells were opened in various places during Ögedei Khan’s rule. This attitude also manifested itself in places far from the center. Thus, Ögedei Khan attempted to erase the traces of the Mongolian invasion that had brought tremendous destruction to Herat after becoming the head of the Mongolian State. In this context, Ögedei Khan had his hands full reconstructing the places that had fallen into ruin during the reign of Chinggis Khan and entered a recovery process. From the outset, however, the construction activities in the Khorasani geography should be said to have been carried out at a lower level, unlike the cities of Transoxiana. Because the Mongols had plundered the towns in the Khorasani geography several times, the region’s development was not at the desired level.

Since the reign of Ögedei Khan, construction activities in Herat have been supported, and the Mongol State provided some support in this regard. The construction works in Herat were initiated by a group of Herat residents who’d returned to the city after the Mongol invasion. However, when considering the conditions of the period, what they did was extremely limited. After Ögedey Khan's reconstruction edict, the construction works in the city progressed much faster. Ögedei’s efforts to bring back the artisans who’d migrated from the region should be evaluated in this context. Another critical step that accelerated the development activities is that the administrators who’d been appointed to the region were integrating themselves and acting alongside the people in the region. Activating water channels to revitalize agriculture in the region was extremely important for the region’s development. In addition, the fact that the administrators personally took part in these activities alongside the people shows that the Mongols’ view of the region had changed. Therefore, through the construction activities carried out in Herat under Ögedei Khan rule, the population in the region increased, and Herat became an important center where artisans carried out their activities in its bazaars and markets. The study is mainly based on Persian sources of the period. However, it also benefits from Turkish and English sources when deemed necessary. In this context, the study first examines the destruction experienced in Herat during the Mongol invasion and under the reign of Chinggis Khan. The study then emphasizes the construction activities that were carried out in the region during the reign of Ögedei Khan and conveys the overall results of this.