The Oregon Theater (not to be confused with the Alaskan War's Columbia Theater) refers to the theater of operations in the Pacific War generally referring to American defensive maneuvers against the invading Japanese in the summer and early fall of 1925 in the state of Oregon and the southern Washington state. Some include northern California as part of the Oregon Theater (especially Japanese military historians) as many attacks on northern California were initiated by divisions that landed as part of the Japanese landings in Oregon, and some military historians also regard the attempted Japanese beachheads on Vancouver Island and the northern Olympic Peninsula to be unfulfilled operations of the Oregon Theather.