The city has a history of over 3,000 years, dating back to the time of the Median empire, when it was known as Ysatis (or Issatis). The present city name has however been derived from Yazdegerd I, a Sassanid ruler. The city was definitely a Zoroastrian centre during Sassanid times. After the Arab Islamic conquest of Persia, many Zoroastrians fled to Yazd from neighbouring provinces. By paying a levy, Yazd remained Zoroastrian even after its conquest, and Islam only gradually became the dominant religion in the city.Because of its remote desert location and the difficulty of approach, Yazd had remained largely immune to large battles and the destruction and ravages of war. For instance, it was a haven for those fleeing from destruction in other parts of Persia during the invasion of Genghis Khan. It was visited by Marco Polo in 1272, who remarked on the city's fine silk-weaving industry. It briefly served as the capital of the Muzaffarid Dynasty in the fourteenth century, and was unsuccessfully besieged in 1350−1351 by the Injuids under Shaikh Abu Ishaq. The Friday (or Congregation) Mosque, arguably the city's greatest architectural landmark, as well as other important buildings, date to this period.

During the Qajar dynasty (18th Century AD) it was ruled by the Bakhtiari Khans.
Under the rule of the Safavid (16th century), some people migrated from Yazd and settled in an area which is today on the Iran-Afghanistan border. The settlement, which was named Yazdi, was located in what is now Farah city in the province of the same name in Afghanistan. Even today, people from the area speak with an accent very similar to that of the people of Yazd.People of Yazd are very famous for being peaceful, strategist, and hardworking. One of the notable things about Yazd is its very family centric culture. According to the official statistics by Iran's National Organization for Civil Registration, Yazd is among the 3 cities with lowest divorce rates in Iran.

Here is Marco Polo writing about Yazd

Yasdi also is properly in Persia; it is a good and noble city, and has a great amount of trade. They weave there quantities of a certain silk tissue known as Yasdi, which merchants carry into many quarters to dispose of. The people are worshipers of Mohammad The holy prophet of Islam .
When you leave this city to travel further, you ride for seven days over great plains, finding harbour to receive you at three places only. There are many fine woods [producing dates] upon the way, such as one can easily ride through; and in them there is great sport to be had in hunting and hawking, there being partridges and quails and abundance of other game, so that the merchants who pass that way have plenty of diversion. There are also wild asses, handsome creatures. At the end of those seven marches over the plain you come to a fine kingdom which is called Kerman.
The Travels of Marco Polo, translated by Henry Yule

Architecture and heritage
Yazd has some of the finest examples of traditional desert Persian residential architecture.
Yazd is of foremost importance as a centre of Persian architecture. Because of its climate, it has one of the largest networks of qanats in the world, and Yazdi qanat makers are considered the most skilled in Iran. To deal with the extremely hot summers, many old buildings in Yazd have magnificent windcatchers, and large underground areas. The city is also home to prime examples of yakhchals, the latter of which were used to store ice retrieved from glaciers in the nearby mountains. Yazd is also one of the largest cities built almost entirely out of adobe.
Yazd's heritage as a center of Zoroastrianism is also important. There is a Tower of Silence on the outskirts, and the city itself has a Fire Temple, which holds a fire that has been kept alight continuously since 470 AD. Presently, Zoroastrians make up a significant minority of the population, around 20,000–40,000 or 5 to 10 per cent.Built in 12th century and still being in use, Jameh mosque of Yazd is an example of finest Persian mosaics and excellent architecture. Its minarets are the highest in the country.

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