User summary, (details from Wikipedia):
Defender of the Crown is a strategy computer game designed by Kellyn Beck. It was Cinemaware's first game, and was originally released for the Commodore Amiga in 1986, setting a new standard for graphic quality in home computer games.
The player takes the role of a Saxon during the Robin Hood era of British history, the goal being, by building forces, fighting battles, participating in joust contests and raiding other castles, to be crowned King of the British.
In 1987 it was ported to DOS, the Nintendo Entertainment System (NES), Atari ST, ZX Spectrum, Amstrad CPC, Commodore 64, Macintosh and finally, the Apple IIGS in 1988. It was later ported to the CD-i.
(Details source: Wikipedia, "Defender_of_the_crown," available under the CC-BY-SA License.