Prominent individual to correspond about pressure put on population (4,5)

'prominent individual' is the definition.
I don't know anything about this answer so I can't judge whether it can be defined by this definition.

'to correspond about pressure put on population' is the wordplay.
'to correspond' becomes 'tally' ('tally' can be a synonym of 'correspond').
'about' indicates putting letters inside.
'pressure' becomes 'p' (abbreviation).
'put on population' becomes 'opp' (I am not sure about this - if you are sure you should believe this answer much more).
'p'+'opp'='popp'
'tally' placed around 'popp' is 'TALL POPPY'.

Can you help me to learn more?