I was just doodling around with this chord progression
Am - Dm - GMaj - CMaj - FMaj - Bbmin - EMaj (or min)
Now most of these chords are diatonic to C except the Bbmin.
Yet i would be inclined to say that the overall mood of the piece and particularly due to the dominant cadence of the EMaj that the piece resolves to an Aminor?
If it was just Am - Dm - GMaj i would say it is definately in A minor (Aeolian) and you could harmonise with this progression in A dorian or A Aeolian or some form of minor/pentatonic/blues form ala Eric Clapton - Old Love. (Although depending on the changes jazz dudes may argue that A dorian over the Dm will make the F# clash with the Dm chord)
But the introduction of the CMaj makes the first 4 chord changes sound very major although the overall peice sounds minor?
Does that make sense? If i were to improvise over the progression without focusing on the chord changes and playing modally but rather trying to hone in on the tonal center, i am not sure if i should be thinking in CMaj or Aminor.
I hope i have not confused you!
Any help would be appreciated.
Cheers