Serf City: Life is Feudal is a somewhat slow-paced German-developed point-and-click title released as The Settlers in the Europe. In Germany (although not in the rest of Europe) it was called Die Siedler. Starting with The Settlers II, it was called The Settlers in America, too.
The Amiga version was released in 1993, while the MS-DOS version arrived later in 1994. The DOS version came on 3 3.5" floppy discs.
A review in Amiga Format magazine cited the original versions' (or at least the DOS one's) maximum simultaneous autonomous units (on then-current hardware) at 64,000. It has 4-player multiplayer and the ability to play against computer players, or watch computer players in a full spectator mode. Players can fight with knights (upgradeable 4 times for a total of 5 levels) that also increase in strength based on their owner's wealth.
The Settlers has spawned 5 sequels, as well as a DS port of The Settlers 2 (although it is just called The Settlers).