All known written sources about Bulgaria and the city of Bulgar were created outside its borders and do not contain a systematic account of its history. These are works by Arab and Persian authors, mentions by ancient Russian chroniclers, and Western European travelers. Mostly, they represent records of their impressions during brief visits to Bulgaria or convey second-hand information. The name "Bulgar" is the Russian variant of the Tatar word "Bolgar." Therefore, in all ancient Russian sources, the names "Bulgar" and "Volga Bulgaria" appear. As a state, Volga Bulgaria emerged in the 9th century, after part of the Bulgars migrated from the territories of present-day Kuban, Crimea, the North Caucasus (Kabardino-Balkaria), and southeastern Ukraine. They had migrated earlier in the 5th century, but the state was formed only in the 9th century. The speed is boundless, just like Russian Post. (Joking, for those times this was a normal time for the formation of a state). A huge role in the establishment of the Bulgars was played by the adoption of Islam in 922. Later, the capital became Bilyar.

In 1236, Volga Bulgaria fell under the blows of the Mongol troops of Batu Khan and became part of the Ulus of Jochi (Golden Horde). The city had a huge developed bazaar, and the city itself was entirely wooden — it was burned down. But it was almost immediately rebuilt due to its advantageous location for trade, unlike other destroyed Bulgar cities. In the 13th century, it recovered from its destruction, and in the first half of the 14th century, it reached its second heyday. It turned into one of the largest cities in Europe with a population of over 50,000 people. It was located at the center of trade routes between the West and East and was famous for its market "Aga-bazar." Crafts flourished in the city: leatherworking, blacksmithing, pottery, jewelry. Bulgar minted its own coins: silver, then copper. The city rapidly developed, and all known structures from that era were built at this time. Bulgar turned into a powerful fortress, surrounded by a moat filled with water, an earthen rampart, and strong oak walls.

In Russian chronicles, the state is called Great Bulgar. But by the end of the 14th century, the Bulgar land itself began to be called Tatar, and the ethnicity in historical sources is already referred to as Tatar. In 1395, Bulgar was destroyed by the troops of Emir Timur. Later, the city began to be restored, but in 1431 it was finally destroyed by the voivode of Grand Prince Vasily II, Fyodor Pestriy. Pestriy exterminated "everyone and everything," and the city remained deserted for almost 300 years, but in 1712 the Assumption Monastery arose on the Bulgar hillfort. The monks used the surviving buildings for their needs.

In the "Extract from the boundary books of the letter and measure of clerk Andrey Mikhailov on the lands of the newly built Bulgar Assumption Monastery of 1712," published in 1871, besides the "surrounding earthen rampart," the remains of which have survived to this day, and internal fortifications — the "small trench where the tsar's house was" — there is a description of more than 70 medieval buildings and structures. Among them are "four round chambers," "an eastern pillar, which even now is eleven sazhen high," "and near those four chambers a fifth round one, in which the Nikolskaya Church is now appointed," "and on the side of those chambers... another quadrangular chamber, in which there are also cemetery stones with Tatar inscriptions," "an eastern pillar seven sazhen high," "near that pillar two quadrangular mosques," "behind the trench a quadrangular chamber," "a quadrangular chamber without a vault," "that chamber was formerly a church, because near it there are many cemetery stones with inscriptions, and the inscriptions resembled Armenian writing."

The monastery was soon built in the center of the hillfort; the surviving mausoleums near the ruins of the Cathedral Mosque ("The Quadrangle") were adapted by the monks into the Church of St. Nicholas and the Monastery cellar.

The most important and pivotal event was the stay of Peter I himself here. In the city of Bulgar, he stopped during the Persian campaign. "The Great Sovereign ordered some buildings, such as pillars and towers, to be measured in his presence; then he was at the ancient city cemetery; he saw more than fifty tombs, or large stone slabs on the graves with inscriptions in various Eastern languages, indicating the different peoples who lived there and the antiquity of the city." In a letter to the Kazan governor Saltykov, he wrote: "During Our stay in Bulgar, We saw that the foundation of the tower (or bell tower) of the old Bulgar building was damaged and needed to be repaired anew; therefore, send there today about twelve stonemasons with their tools and several barrels of lime, and there is enough old stone there; also the bridge and the old one need to be repaired."

In the 18th century, numerous reconstructions took place in the city of Bulgar. For example, in 1732–1734, the Assumption Monastery was built on the site of the Khan's court and the Cathedral Mosque. Tombstones were used for the foundation. In 1767, a year before Pallas's expedition, the Bulgar hillfort was visited by Catherine II. In particular, she wrote: "We went to the shore to see the ruins of the ancient city of Bolgary, built by Tamerlane, and indeed found remains of large but not very good buildings, two very tall Turkish minarets, and everything left here is built from very good slabs; the Tatars have great respect for this place and come to pray to God in these ruins." Of course, the Empress was mistaken regarding Tamerlane. Tamerlane was not the builder but the destroyer of Bulgar. Originally, the city of Bulgar in the form of yurts was founded by Almush's father, Khan Shilki (Silki), back in the 9th century. More precisely, the ancestors of Almush lived here in the second half of the 8th century.

Under Almush, wooden and the first stone buildings began to appear. The invasion of the Golden Horde destroyed the cities of Volga Bulgaria. But soon Bulgar was restored. This was under Batu. In 1242–1246, Khan Batu himself lived in this city. Around the same years, several other cities were built. For example, Ester-khan (Chuvash: Aştărhan "Astrakhan") appeared. Then the headquarters of Khan Berke were located in Bulgar and Sarai. Thus, in 1236, the capital of Volga Bulgaria, Bulgar, was destroyed but soon restored. Therefore, all stone buildings and inscriptions preserved there now belong to the era of Mongol rule and later times.

By the time of Pallas's arrival, 44 structures still remained on the hillfort territory. He provides a description of the historical objects he saw. "The most notable of these is the tower or minaret made of hewn stones, somewhat more than 12 sazhen high, built according to the model and proportion shown in the sixth plate under the letter A, and it still stands intact. One ascends it by a round staircase of 72 steps, each about a Paris foot high... The doors to the tower are on the southern side, and large iron hooks are visible in the wall on which the door hung. Small holes remain in the tower walls, through which light passes, indicating the staircase path. Near this tower, within an irregular quadrangle, are the ruins of a large stone building with thick corners, which may have been a large mosque. This building consists of uneven, poorly hewn but very tightly stacked limestone, sandstone, wild, and gypsum stones, which were carefully taken from the mountainous bank of the Volga." "Almost 80 sazhen further to the southwest stands another small quadrangular building made of wild stone, tightly stacked; however, its vaults have collapsed on one side... Much more notable and extensive was the building located in the middle of the former city and surrounded by many foundations; the main structure is still visible. Its excellent architecture deserves to be illustrated."

"But it is difficult to determine what this building was for. The peasants call it the judge's house; and I have no reason to consider it anything else." "Many ancient tombstones with Arabic and some Armenian inscriptions were found in Bulgar, some of which are now partly used in the foundation of the new church of the Assumption Monastery, and partly lie near it on the ground." The inscriptions on some of them indicated that the deceased came from the Persian province of Shemakha, and one from Shirvan. Naturally, these people arrived in Volga Bulgaria on business. One can also conclude about its great trade from the silver and copper small coins that peasants' children still collect in the local fields. Among the silver coins, those with quite good Arabic and Kufic inscriptions are often found; such coins are minted from pure silver; they are deliberately thick and usually no larger than the thumbnail. But there are many made of poor and brittle silver, minted very thinly and impurely. These coins have either stars or other decorations on one side, and on the other side, high dots and a circle with an arbitrary sign almost the same as those used by Bashkirs and other illiterate peoples today instead of a handwritten signature. I provide drawings of two such coins; but on copper coins, such signs are much more numerous, usually in a triple triangle.

Pallas visited the Bulgar hillfort eight and a half centuries after Ibn Fadlan and shortly after Peter I and Catherine II. By Pallas's arrival, there were 44 structures here. The drawings and descriptions of the Great Minaret, the Khan's Mausoleum, and the Black Chamber are of enormous historical importance. The tombstones and coins found are of undeniable interest. All surviving buildings date back to the Golden Horde period. Today, this place houses the magnificent "Architectural and Historical Complex Bulgar," restored based on surviving images, among which Pallas's drawings have fundamental significance.

Sources:

Bulletin of Chuvash University: https://www.chuvsu.ru/wp-content/uploads/2020/04/2018_2.pdf

http://welcome2kazan.ru/okrestnosti/bolgar.php

Abdullin Kh.M., Baranov V.S., Bugrov D.G., Sitdikov A.G. Museum of Bulgar Civilization. Vol. 3. The Discovery of Ancient Bulgar