Who was Subhadra in her previous birth ?

Subhadra was the sister of Lord Krishna in Dwapara Yuga. As a result of her past good deeds, subhadra was born in a close familial relationship to the Lord Krishna. Subhadra was born to Rohini after King Kamsa was killed by Lord Krishna. After the kurukshetra war, Sri Krishna asked Arjuna to take subhadra into the deep waters and push her into it and return without looking back. Thus ordered, Arjuna took subhadra into the deep waters and pushed her into it. In his return journey Arjuna was curious to know why the Lord has ordered thus.  Almost reaching the shores, due to uncontrollable curiousity, Arjuna looks back to find a huge demoness in the waters.

Surprised with what he saw, Arjuna approached Lord Krishna and enquired about the demoness. Lord Krishna told Arjuna that in the past life, Subhadra was the demoness Trijata, the daughter of King Vibheeshana of Lanka and a Niece to the Demon King Ravana. In Treta yuga, Trijata helped sita in living at peace in the ashoka vatika.Thus pleased, Lord Rama (the previous Maha Vishnu incarnation) gave her a boon to be born in a close familial relationship to him in the next life. Hence, Trijata was born as Subhadra and lived until her store of good deeds exhausted and thus has turned again into a demoness.

             Sri Satchidananda Satguru Sainath Maharaj ki Jai !