I specialise in Historical Music performance... and I was surprised by the number of people who are 432Hz advocates...

Historically it is as you say... the was a hodgepodge of both pitches and temperaments (mostly tuning from C and not A anyway....). In the modern historical performance movement, we have adopted several "standard" pitches of A= 392, 415, 430, 440, 466Hz depending on what sort of music (nationality and style) that we are playing and often a historical temperament that is appropriate as well! This is a bit of modern hack so that concerts with multiple styles and genres don't have to have a different tuning for each piece!

Anyway, historically musicians tended to tune to the church organ... which could have been anything from town to town depending on builder, the season... and how many times it had been cut down to "tune" the temperament....

Anyway, the 432Hz thing drives me nuts! Temperament, yes that makes sense... but the absolute pitch of the notes? Bleah....