"* "Netherlands New Guinea"? Are you trying to figure out the old term for the region? The name as it was actually called by people during the 20th century until 1962, was Dutch New Guinea; though I think "Netherlands New Guinea" may have been the offical designation since WW-II. 
 The reason westerners then started to call it ""West Papua"" was because it was no longer 'Dutch', and ""West Papua"" is the shorest & easiest description so you knew percisely where you were talking about; Indonesia was using something that no-one could pronounce or remember straight. It's only coincidence that it was also what the Papuans had decided they wanted their nation called. ""West Papua"" remains the simplist geographic description that people will most commonly try to refer to it as.
 A person says he's from West Papua, you know what he means; he says he's from Papua, you assume he's form PNG.
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