Popularity of the Greek monarchy before Constantine

[CSENYC]

How popular was the Greek monarchy in the 1950s and early 1960s, before King Constantine?

Was there always a large split in Greek society over the monarchy? Was the monarchy basically imposed by the US and UK after WWII, or were Greeks always generally supportive of it?

I recall that the monarchy was overthrown in the 1920s and then restored, in what I'd guess was a sham referendum in the 1930s, and after WWII the US and UK played a role in restoring it then?