there are two approaches to damp. You either build something that breaths so that moisture moves through the building or you build using materials which are impervious to damp.
Old buildings are built using natural materials and breath. So lime mortar (Cement not invented till 1800's), limewash, linseed or similar oils, oil based paints. The key point being that any moisture which gets into the structure of the building can get out again easily. This applies to everything from cob, tudor wooden frames, stone, etc. Old bricks were fired at lower temperatures and had higher moisture content.
Modern buildings surround the building with materials which (hopefully) prevent the passage of moisture, portland cement, concrete high temp fired bricks, etc.
It is a fact that most damp probs are nothing to do with rising damp. !st thing to check is where water could come from, so gutters, drains, condition of render, pointing, brickwork, roof, floor levels, ventilation, building use (gas burns to produce water - thats why lots of olp peoples houses seem damp - gas fires on all the time and minimal ventilation)
Problems can be made much worse by applying the modern approach - chemical dpc etc - in an old building. Stop the breathing by using opc render, concreet or gypsum internal finishing etc and you get problems. moisture that should disperce from the entire structure is suddnly restricted to small areas and damp becomes a problem.
Concrete floors with a membrane mean that rather than a slow permeation of moisture through a stone floor yo uget damp in the walls.
Also if part of the modern type surround fails, so cracks in render or such like, then the moisture which then gets into the building cannot get out and you have a damp problem.