In June 2011, while clearing out his late father’s home, Oakland resident Barry Braz found a treasure. In a leather envelope, tucked in a closet in the San Jose, Calif., home, were letters in Portuguese written in the 1950s and photographs taken in the 1890s on the Portuguese island of Flores. The letters were stuffed into one paper envelope with a Flores return address. The letters and photos sparked a yearlong adventure that ended with Braz, 66, dining in August at the same address with 10 relatives. Only one spoke English. Wild hydrangeas give Flores, Portuguese for “flowers,” its name. …