In last night's fourth season premiere, Sookie (Anna Paquin) returned from the fairy world to discover that a year had passed in Bon Temps.
Ball told TV Line: "We wanted to get all of our characters into somewhat of a new place. To give Jason (Ryan Kwanten) time to have actually become a sheriff's deputy. To have Bill (Stephen Moyer) be the king. To have Arlene (Carrie Preston)'s baby be born."
He continued: "We were talking about Sookie being in Fairyland... and it seemed like a really organic way to kickstart the show so that it would be in a new place when she got back."
The showrunner also defended the decision to have Tara (Rutina Wesley) become a lesbian in the time gap.
"Look at Tara's history with men," he suggested. "If anybody has a reason to try something new, I think she does. It didn't seem like it was that outlandish given her history and who the character was."
Ball added that Rutina Wesley was "totally willing" to explore a different side to her character.
"I count my blessings with this cast all of the time because everybody is pretty fearless," he said. "Everybody is pretty game to do just about anything."
True Blood continues on Sundays at 9pm on HBO.
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Watch a trailer for the fourth season of True Blood below: