[3] Vajira was born a princess of the Kingdom of Kosala and was the daughter of King Pasenadi and Queen Mallika.
[5] When the princess was born, her father was apparently disappointed on hearing the child was a girl, but Buddha assured him that some women were wiser than men.
[5] The events which led to her betrothal and eventual marriage to Ajatashatru was that her husband waged a war against her father's kingdom after Bimbisara's death, the cause of the conflict being the revenues from the estate of Kashi, which was given as a dowry to Kosala Devi in her marriage to Bimbisara.
After Kosala Devi's death, Pasenadi immediately confiscated the revenues of the estate of Kashi, which had been settled on her as "pin-money", this resulted in hostilities between him and Ajatashatru.
[6][8] The estate of Kashi, which had been the reason of the conflict, was given to his daughter, Vajira, as a part of her dowry in her marriage to Ajatashatru.