Sage Vyasa compiled the four Vedas, the Mahabharata and the Eighteen Puranas. The name Veda Vyasa refers to Krishna Dwaipayana who was the son of Satyavati and sage Parashara - this is before Satyavati married King Shantanu of Mahabharata fame.
"When the second millennium Dvapara Yuga overlapped the third Treta Yuga, the great sage Srila Vyasadeva was born to Parashara Muni in the womb of Satyavati, the daughter of Vasu (the fisherman)." (Shrimad Bhagavatam 1.4.14)
In Srila Vyasa's childhood he was called Krishna, because of his dark complexion, and because he was born on an island at the confluence of the Sati and Mati Rivers he was called Dwaipayana. After dividing the Vedas he got the name Veda Vyasa. Srila Vyasa's appearance was on the twelfth day of the light fortnight in the month of Vaishaka (April-May), called Vasanta Dwadashi.