I am fairly sure there was a separatist Idel-Ural government in Kazan c.1918. The flag of Idel Ural was blue with golden emblem in the upper fly corner. The first depictions of the civic emblems occur on a seal of Ivan the Terrible, and, with insignificant alterations in details, on other monuments of the sixteenth and the first half of the seventeenth centuries. This depiction, published in the Titulary , fully conforms to the law. But the Kazan coat of arms possesses an earlier origin.
Legend speaks thus of the foundation of the city.
Kazan was built on a place where there was a multitude of snakes. A Tatar sorcerer lit bonfires and spoke magic words. On the site thus liberated people built a city. However, they were unable to live in peace, as the snake-king who had settled nearby brought misery on them. Fortunately, in the city there appeared a mighty magician, Hakim, who was able, by mighty conjurations, to kill the snake-king.