From the 1 to the m4
Read part one here
Lennon & McCartney first used this chord progression (E to Am in the key of E) in the verse of That Means A Lot. The song was intended for the Help album but didn’t make the grade and was given to P.J. Proby (you can hear the Beatles version on Anthology 2).
When Rubber Soul came along they had another stab at using (it on the verse to What Goes On where the progression move from an E7 to an Am (I7, iv)
The E7 other day I saw you
As I Am walked along the road
But E7 when I saw him with you
I could Am feel my future fold
The results were similarly underwhelming.
Finally they hit gold with the bridge of She Came in Through the Bathroom Window.
A Didn’t anybody Dm tell her? A Didn’t anybody Dm see?
This little change also crops up in the chorus of The Continuing Story Of Bungalow Bill –
C Hey G Bungalow C Bill, Fm what did you C kill, Fm Bungalow C Bill (I, V, I, iv, I)
The song then momentarily transposes to A and repeats the same progression.
That kind of wraps up my series on this unusual but very Beatlish chord, except that I've found about 5 more songs that I missed the first time around. You can find them and more here.
And in the meantime keep putting this 'out of key' chord into your own songs until it becomes a natural option.
Read the other posts about the minor 4 chord here