The Netherworld of the Force was the place the souls of Force-sensitives apparently went after their physical bodies died. Qui-Gon Jinn went to this realm after dying, but managed to return from it back to the physical universe as a Force ghost. Anakin Skywalker learned this from Obi-Wan Kenobi after he died upon the Second Death Star. Obi-Wan's spirit departed to this realm after having one final talk with Luke Skywalker in 9 ABY. Yoda was also seen in this realm, where he reunited the recently deceased Vila with her brother Denin and promised he would train both of them.