Must be a country's leader (for governments with both, either head of state or head of government is fine, even if ceremonial) as of November 1st, local time, or become such by question close. Doesn't need to die "in office".

Edge case example: a president who leaves office the third day of the month but then dies the fifth 

Presidents, Prime Ministers, Monarchs, etc. 

(most of these are valid, see caveat below)

Caveat: members of a council that is itself the Head count, but "deputies" "vices" and "assistants" where there is a higher seat do not.