Christianity in Australia and Oceania

Throughout the countries of Oceania, Christianity is the predominant religion with the most worshippers compared to other religions. However, not all countries share the same predominant Christian denomination. As shown below, some countries are Catholic: AUSTRALIA, KIRIBATI, the Federated States of MICRONESIA, and PALAU. Considering PAPUA NEW GUINEA has a myriad of languages, nations, and ethnic groups, it may be surprising that an "invasive" religion like Christianity is more popular than indigenous beliefs/religion! This unusual principle practically applies to every Oceanic country below because former colonizers from Europe brought the Christian religion and converted native people into Christians.
Below is a complete list of predominant Christian denominations in Australia and Oceania.
Australia --- Catholic
Fiji --- Methodist
Kiribati --- Catholic
Marshall Islands --- Protestant: especially the United Church of Christ (Congregational in the Marshall Islands) and Assemblies of God
Federated States of Micronesia --- Catholic
Nauru --- Nauru Congregational, followed by Catholic
New Zealand --- Anglican
Palau --- Catholic
Papua New Guinea --- Catholic
Samoa --- Congregationalist
Solomon Islands --- Church of Melanesia, followed by Catholic
Tonga --- Free Wesleyan Church
Tuvalu --- 97% Church of Tuvalu (Congregationalist), followed by Seventh-Day Adventist
Vanuatu --- Presbyterian