tinyE: Well said. I consider it a slightly more complicated RTS. Think AOE with some extra middlemen involved. In AOE you build the barracks and get your troops. In Settlers you need the barracks, and the weapon smith, and the processed materials to make the weapons,
then you get your troops.
Yeah, well it's somewhere between an RTS and a sim, I suppose. The actual combat part is very abstract and indirect. As you say, the point of the game is building and managing the infrastructure that makes combat possible. A classic RTS usually has only one or two resource types. Settlers II has... Shit, I don't know. 60? It's all about managing the chain of production. You need weapons. So what do you need to
make weapons? Well, you need an armorer. Okay, so what does
he need to make weapons? Well, he needs processed iron and coal. Oh, and tools. So you need a blacksmith to make the tools, an iron smelter, an iron mine and a coal mine. Ah, but the iron smelter uses wood for fuel, so you need a sawmill and some woodcutters. And a forester, to plant new trees. And miners need food, so you need some farms and a baker, maybe some hunters and fishermen. And to build all these buildings we'll need a shitload of wood and stone, and we need an efficient network of roads to transport resources between the buildings.
It all sounds extremely complicated, but the thing is that you start at the other end of the chain, with just a few simple buildings. Then you find out what those will allow you to build, so you expand the infrastructure and build those, then get access to new ones, expand again, and so on. While the game mechanics are nothing like Civilization, the game itself is quite reminiscent of it. It is very slow paced, and you spend a lot of time building things and climbing up the technology tree.
Man, I really need to play Settlers II again soon.