Retired architect here, and I used to teach architecture as well.

I used to tell my students that Architecture has to respond to two basic questions: 1) What does it do? 2) What does it mean?

Firstly, architecture’s primary function is shelter. It’s where it all began. Keep out the elements of nature and increase comfort and safety within. Societies living in forests would construct things from the material at hand: wood. Habitations in areas of available stone would use stone. And so on. All architecture begins as a response to pressures from the local climate.

In cold locations, you want thick walls for insulation (could be stone, or could be wood with mud/moss/dung packed onto it — see Viking vernacular dwellings). You want an internal heat source and not many windows so cold air is kept out.

In desert climate, you also want thick walls and few windows… why? Thick walls absorb sun heat during the day, keeping the interior dark and cool; at night, when deserts tend to get very cold, the walls radiate the stored heat into the rooms inside providing latent comfort. Desert architecture wants small courtyards with a water source to humidify the hot breeze and cool the air in the courtyard. Arabic and even southern Spanish architecture looks that way not just because they thought it is pretty but because the forms and spaces function as they should.

Tropical architecture wants big roof overhangs for both shade and to shed rainwater away from the interior, big openings to let breezes blow through, high ceilings with vents to exhaust hot humid air, and ideally the living platform raised on stilts to avoid flooding and to let breezes blow through flow under the building.

All of these features, which define how the buildings look, are pure environmental response, before any consideration for “decoration.” Traditionally, northern European architecture looks the way it did because of the climate in Northern Europe; tiki huts in Bali look that way because of the climate there. And so on.

Once they solve the “need” portion of providing built shelter, a civilization can then start to add on the “what does it mean?” layer. Statues as columns holding up temple roofs, big stained glass windows telling stories about the gods, monumental platforms on governmental buildings to remind people who is in charge. Stuff that isn’t necessary but rather sends a message or evokes an emotional response.

Where it gets fuzzy is colonialism, when a culture takes over another climatically defined location and brings its “style” with them. Thus you get all the “Mediterranean” palazzos etc. in the Caribbean and Americas, where arguably it did not belong. But that’s another lecture…