Conclusion: While the majority of the Morrowind Theme is in Eb Major the traditional approach would be to call it C Minor because it ends in C (and starts in C, even though that doesn't matter historically and systematically at all).
What key is the morrowind Theme in?
Morrowind Theme Song is written in the key of C Minor. According to the Theorytab database, it is the 2nd most popular key among Minor keys and the 6th most popular among all keys. Minor keys, along with major keys, are a common choice for popular music.
What instruments are used in the Morrowind theme?
Harpist Plays the Morrowind Theme and It Is Awesome. The harp may not be the most obvious choice of instruments with which to interpret the Morrowind theme but I have heard it [and seen it] and it is stirring and beautiful.