From Scenario League Wiki
It is unknown when exactly the first people settled in the South Sea islands. Melanesian settlers from modern-day Indonesia are thought to have reached New Guinea as early as 2000 BC. The highly advanced "Lapita culture", named for a place in New Caledonia, emerged around 1600 BC. Two further groups, the Micronesians and the Polynesians, soon appeared. The Micronesians settled in the Marshall Islands, the Carolines, the Marians and other island groups nowadays known as Micronesia. The Polynesians descended from the Fidji, Tonga and Samoa islands and soon expanded further eastwards, as they were being pushed by the Melanesians, who were reduced to New Guinea and the surrounding islands.
The Polynesians soon became the greatest seafarers the world had ever seen, as they had only 'primitive' navigation methods and narrow boats, but colonized a territory that stretched from Hawaii to the Easter Islands, and New Zealand (where they are nowadays known as the Maori). Sadly, little of these cultures is left, especially in the smaller islands, as they fell victim to the European invasion and Christian missons. The South Seas became subject to foreign imperialism, mostly between the French, Spanish, and later Americans, Germans and Japanese.
All seven civs appear in this scenario, but only five are intended for play.
If you want an easy game, you are directed to the Polynesians and the Maori.
The Polynesians start with most technologies, and three cities, and a lot of advantages concerning trade and travel. This is to reflect the importance of their culture for the rest of the southern Pacific area.
The Maori, being Polynesians themselves, have the same technological boost, plus two wonders, whereas all others (in exception of the Papua, who have none) have only one. Their enviroment, meant to reflect the Northern Island of New Zealand is very different, being a large landmass rather than many tiny islands. Whether this is more difficult or easier is up to you, it's different in any case.
Next would be the Melanesians and the Micronesians. Both have certain advantages and disadvantages.
The Melanesians have large islands, and therefore are likely to develop a large population. However, it isn't as likely as with others that they will have an easy time catching up with the development, because they aren't very advanced and their production is rather low.
The Micronesians have a huge amount of tiny atolls, which have great shield output, but very little trade and virtually no food around. Growth is a huge problem to them, and they will always have a difficult deciding whether it's north -with very productive cities and little danger, but much isolation- or south with none of the above.
The Papua will have a very hard time. They are the most isolated civ, having a large but dangerous island to explore and colonize. Once they've reached an agreeable situation, most other powers will probably have gotten a huge head start.
Rules, Details and Info
This scenario is basically a completely modified standart game, and should be played as such. To make the AI more agressive, though, the capital cities of the Polynesians, Melanesians, Micronesians, Papua and Maori are set as objectives. Therefore, the scoring system isn't the same as in an original game. This isn't very much of a problem, as I believe the scores according to the original system wouldn't have been very accurate compared to real achievements in the game.
I think it's time to tell you about the map. It's ugly. Well, that may not be true. This scenario is set mostly for naval strategy, with very little land and very much water. Large land masses can only be found in the south of the map, but these territories (New Zealand and New Guinea) are already occupied by the Maori and Papua. So, why not build your cities on one of those nice and empty little islands... empty? Well, they may look so at first. But you'd better double-check. At rare occasions, you will see a little settlement on one of the larger islands. Those are tribes that reached this island before you. They are hostile. Fight them.
Sometimes, however, the island is already populated without you seeing it. The people living there are fierce, bloodthirsty cannibals. If you leave them alone, they will leave you alone, but having cannibal neighbours isn't such an attractive thing. Sending out your fearless warriors against them is a good idea. However, you never know if the island is inhabited by cannibals or not, unless your troops actually try to set foot on it. You have to live with it.
Well, settling down beside one of those villages until you have the power to destroy them is always an option. Sadly, they often occupy the more beautiful settling place. More sadly, you are usually left with a piece of land unprotected against the forces of nature. A flood may suddenly make all your units and cities perish. You have to live with that, too. Especially because it occurs more than once in a spot most of the time.
Having said that, beware of lower terrains. Higher places aren't that safe either, though. Maybe you have heard of the pacific "Ring of Fire", a ring of volcanoes and earthquake territories along the border of the pacific plate. Here, this is represented by the Melanesian islands. Volcanoes have the tendency to errupt and turn the territories around into rubble. They do this only once, and when you spot some rubble, settling down near it is quite productive. But if you see a volcano that hasn't errupted, beware of it. You never know which ones might errupt, and which ones don't (unless you look into the events file, which is strongly discouraged).
Concluding, be careful with islands that have volcanoes on them, or such that are three squares or more in size. Floods will occur in light jungle, swamp and grassland squares (though not on NZ and NG, and not those islands you start on), and will turn one terrain square into swamplands. They might do this again and again, so be careful. You should better check out if everything is still there at the start of each turn.
Each civ, in exception of the Papua, starts out with at least one WoW. These are meant to suggest the role the certain civ is meant to play. You can easily find this out by consulting the pedia. The same goes for any stats, such as units, improvements, advances, terrain, etc. You should really do so, though, as it's important for you to know.
This scenario is propably more suited for multiplayer games than for single player ones. It will definately be more interesting, as the AI propably screws up most of the carefully planned game concepts you are to find out. Revealing them all here spoils this game entirely. They aren't hard to find out though.