It's the closest D&D really has gotten to D&D Lord of the Rings without it being Lord of the Rings.
You had it all there, the Dark Queen (Dark Lord), the servants of the Dark Queen such as the Dragonlords (aka...Ring Wraiths and other leaders), the Solamnic Knights (aka...Gondor), the party (aka...fellowship) which breaks and separates and goes on their separate adventures, Helm's Deep...I mean the High Clerist Tower, etc...etc...etc.
If one wanted D&D with High Epic Fantasy, Dragonlance was the defining item for awhile....and for some, it still is.