Complex sentence: Earthdance was founded in 1997, by event producer and music artist Chris Deckker (Medicine Drum, Return To The Source), who produced the global event until 2009; and the Earthdance Northern California Festival from 1999 until 2011.
Split into simpler sentences: Earthdance was founded in 1997, by event producer and music artist Chris Deckker (Medicine Drum, Return To The Source), who produced the global event until 2009. Deckker also produced the Earthdance Northern California Festival from 1999 until 2011.