Both the Hawaiian and Pacific Collections have a great many historic newspapers, dating from the 19th century through present. Many are in microfilm, and most have not been indexed, meaning that if you're searching for a specific event, your only option may be to go to the microfilms and begin reading papers dating from the period you're interested in. However, some have been digitized, and in these cases are searchable and readable online.
Hosted by the National Library of Australia, TROVE searches across a vast array of digital content produced by numerous Australian institutions. Digitized newspapers cover the years from 1803 to 1954.
There are many institutions with digital repositories where you can find a wealth of Pacific research content. These repositories are full-text searchable, so a good strategy is to do multiple searches with different combinations of keywords.
A digital institutional repository of the University of Hawaiʻi at Mānoa (UHM), and managed by the UHM Library. Scholarspace contains material produced by UH-Manoa affiliates (students/faculty/staff) as well as material produced by the East-West Center (a federally funded agency located on the UH-Manoa campus).
Digitized from the full published holdings of major libraries across the United States and abroad. Includes a good selection of Hawaiʻi and Pacific titles. Allows you to search within the text of many of the books, but only books published before 1923 will be available online in full. Books published before 1923 are in the public domain.