Legend of martenitsa

Martenitsa is a Bulgarian tradition related to March 1, which has its origin in the establishment of the Bulgarian state in 681 AD. Mart is the Bulgarian word for "March" (Bulgarian:март, mart)
The month of March, according to Bulgarian folklore, marks the beginning of springtime. Therefore, the first day of March is a traditional holiday associated with sending off the winter and welcoming the spring.
The tradition is similar in many ways with the Romanian custom of Mărţişor, celebrated on the same day.
Legend of the Founding of Bulgaria
Khan Kubrat’s five sons went hunting accompanied by their sister Houba. When they reached the River Danube they saw a silver stag. Mesmerized, the men did not dare shoot at him. The stag crossed over to the opposite bank of the river showing them there was a ford.
A bird flew to them bringing bad tidings. Their father, the founder of Old Great Bulgaria was on his deathbed. In his last hours Kubrat wanted to tell his offspring—Bayan, Kotrag, Asparukh, Kouber and Altsek—not to sever the still tenuous link between the different Bulgarian tribes. His sons vowed to defend Bulgaria.
Soon after their father’s death, the Khazars invaded their lands. The Khazar's Khan Ashiba succeeded in conquering the capital Phanagoria. Houba, Kubrat's daughter, was taken prisoner by Ashiba. Hoping to give her brothers a chance for freedom, Houba tried to commit suicide but was stopped by the guards.
Her brothers kept their vows in different ways. Bayan stayed with his sister and recognized the supremacy of the Khazars. Kotrag went northwards, to the River Volga, while Asparukh, Kouber and Altsek went south to search for a land without oppressors.

The brothers who left secretly arranged with Houba and Bayan to send word by a golden thread tied to the leg of a bird if they were able to find a free land. One day a falcon sent by Asparukh flew into Houba's room and she and Bayan quickly made plans to escape. Just as they were looking for a place to cross the Danube River, Khazar pursuers spotted and rushed toward them. Trying to find a ford, Houba let the falcon free. She tied a white thread to its leg and handed it to her brother.
Just as the bird was about to take off, an enemy arrow pierced Bayan and his blood stained the white thread.
While both Bayan and Houba managed to reach the land Asparukh had found (present-day Bulgaria) they were at the point of death by the time they did so. Asparukh welcomed his dying brother and sister. He tore the pieces of white-and-red stained thread and adorned his soldiers with them.

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