(CNN) - When Bob Bergdahl was formally introduced to America in the White House Rose Garden beside the President, he was startling to see and hear at first: the father had seemingly morphed into an Afghan tribesman, wearing a long beard and even speaking Pashto.
The transformation of the former UPS delivery man was five years in the making in the mountain valleys of Idaho, sparked when his son Army Sgt. Bowe Bergdahl was captured by the Taliban in Afghanistan in June 2009.
In the half decade that he and wife crusaded for their son's release -finally won this past weekend - Bob Bergdahl journeyed deep into the meaning of his son's captivity and war itself, according to media accounts.
He immersed himself in books about Afghanistan and its Pashto language, to speak to his son's captors if only from afar. When it was over, he emerged as someone apparently transformed by his odyssey to save his son.
"I am your father, Bowe. To the people of Afghanistan, the same," Bergdahl said during the Rose Garden announcement of his son's release.