The announcement comes just a year after Dimon tapped Miller (right) to head the No. 2 U.S. bank’s international push. Dimon said last June that creating that job would “augment — not replace — business lines around the world, helping them accelerate and prioritize their efforts and their investments for growth.”

So much for that, though. JPMorgan Chase (JPM) suggested Tuesday that after a year at the helm of this new ship, it was Miller who decided to run up the white flag. The bank said she made a “recommendation that responsibilities for international activities be embedded back into the businesses.”

The embedding will take place under Jes Staley, another top Dimon lieutenant, who will take over Miller’s responsibilities. Miller, meanwhile, departs with polite applause.

“Heidi has been a valued member of our Operating Committee and a trusted adviser to me over the years, and she has also served as a role model to countless others inside and outside of our firm,” Dimon said.

JPMorgan didn’t say what Miller might do after leaving the bank in early 2012.

“We’ll miss her greatly and wish her all the best in whatever she chooses to do next,” Dimon said.