Krishna Janmashtami - Birth of Lord Krishna and the story behind his birth.Lord Krishna born in Shrvaana masa, Shukla paksha, Ashtami day, Rohini nakshathra. Lord Krishna born in the middle of night, so this festival will be celebrated 2 days. People worship first day expecting birth of jagadhodaraka and second day with joy on birth of Lord Krishna. Vasudeva and Devaki are real parents of Lord Krishna, but was brought up by Nandaraja and Yashodha. Lord Krishna born in prison where his parents were kept by his uncle, Kamsa with fear that a son of her sister, Devaki will kill him as said by devavani. So, Kamsa did let Lord Krishna's parents to live freely. He kept them in prison as prisoners and went on killing the babies born to her sister and even kept his own parents in prison as they opposed it. It is a great miracle that how Lord Krishna could escape from his uncle. The day he born all prison staff were made to pass out and Vasudeva kept his son in a basket and carried over his head and crossed the river on a heavy rainy day with 7-headed snake covering the basket as umbrella and reached the Nandaraja's house. The same time, Nandaraja's wife Yashodh gave birth to a baby. Vasudeva exchanged his son with baby born to Yashodha. When Yashodha gained consciousness after delivery she found Lord Krishna next her and believed it as her son. This is how became Lord Krishna became son of Yashodha. It is also believed that Yashodha had asked Lord Vishnu in her earlier janma to give her a chance to do seva for him, so Vishnu blessed her as in his next avathar he will become son of her and she will be given a chance to raise him as a seva.
Krishna had very naughty character in his childhood days and it is also believed that he is a strong sign of love, so even now Radha-Krishna stories are famous as love stories.
Butter is the most favorite food for Krishna, so this will be offered on Krishnashtami as offering along with different varieties of puddings, deserts, and fried foods like, chakkuli, rava ladoo, etc., Tulsi is the famous offering for Krishna. Balagopal foot prints were drawn in each house on that day signifying his arrival into their houses and Lord Krishna's idols were worshipped with various kinds of fruits, flowers, foods, leaves, and abhisheka offerings.