North West Pacific Islands

The North West Pacific Islands were regions were captured by Australian forces during World War I. This included German New Guinea, Nauru and the Bismarck Archipelago.

 File:NW Pacific Roo.jpg|1915 9d roo with two longtailed "S"s File:NW Pacific KGV.jpg|1922 4d George V with two normal "S"s File:NW Pacific perfin OS.jpg|1919 5d OS perfin 
 * In 1915-16, Australian stamps were overprinted N. W. / PACIFIC / ISLANDS.. The "P" is directly over the first "S" of "Islands". This includes various values of:
 * George V heads with second/pointed top crown over A watermark.
 * Roos with first/wide crown over A watermark.
 * Roos with with third/narrow crown over A watermark.
 * In 1918, 2 overprinted values were surcharged One Penny.
 * In 1918-22, a new version of overprints was issued, with the leg of the "P" over the space between "IS" of "Islands". This includes values of:
 * George V heads with second/pointed top crown over A watermark.
 * Roos with with third/narrow crown over A watermark.
 * New George V values in changed colors with second watermark.
 * A ½d George V with multiple narrow crown over A watermark.

There are two different overprint "S"s, one with a long tail ( or "wide S"). There are three types: "S"s normal, first "S" long tail, both "S"s long tail. Specialists collect horizontal strips with different overprint combinations; some combinations are quite scarce.