Getting starting with GIS for fictional worlds - how to build initial basemap/data?

[AzureWings]

Thanks - and I do see what you mean, that much of the relational analysis capabilities might go rather unused in a fantasy context (though I'd hesitate to say they'd be entirely useless - the reason I was interested in using GIS for fantasy maps is that for some settings I'd had a number of different metrics I'd wanted to put together choropleth or other thematic maps for over the same geography - it might be interesting to see if I could use that sort of analysis on a regional scale to try and put together better correlations between, say, concentrations of population ethnicities and proximities and which lingua franca/trade languages are dominant in what regions as a result).

Hai-Etlik actually did cover the projections bit to an extent which was pretty neat (they had a thread on here about how to define a non-Earth CRS) so I wouldn't say projections for a fantasy world (if of course drawn directly from real map projections) are necessarily off the table .

As regards my original question, I guess - then to confirm, just drawing around in QGIS itself is a fine way to create base vector data - regardless of said data's actual quality, it would be in principle usable as a base to reference other data with respect to? I guess my real confusion was that from the information I could find I couldn't really tell whether there was or wasn't any 'special sauce' of sorts to a base dataset, since nothing really talked about constructing one, just fetching them from elsewhere.

[Shenanigans]

In summary, yes, you can just draw vector shapes. Generally speaking, any sort of special sauce is in the attributes table and the queries that use that data. ArcGIS is notorious for charging extra money for versions of the program with better analysis tools. With a properly populated table, your example of ethnicities and language use is totally viable.

Hopefully that helps. It's pretty neat software. I hope you have fun with it!