The Diocese of Nesqually was established in Vancouver , Washington , on May 31 , 1850 by Pope Pius IX . The new diocese 's territory was carved from the former Diocese of Walla Walla , which had been abandoned and its territory administered from Oregon City in the wake of the Whitman massacre . Augustin-Magloire Blanchet , the first bishop of the new diocese , dedicated a cathedral in honor of Saints James and Augustine within Fort Vancouver on January 23 , 1851
Whitman massacre
Whitman massacre
St. James Cathedral (Seattle)