By Alex Richards
While the question of audience forms the bedrock of mapmaking, and the question of programme is, naturally, the first that must be answered; it is the question of base-maps that is, almost certainly, the most frequently asked by budding cartographers.
What is a Base-map?
A base-map is exactly what it sounds like- the map you use to base your own map on. Behind this, however, is a great diversity of options which can broadly be considered as fitting into two categories. First are editable maps- those where the new map is created directly from the base-map itself, ranging from adding colour to an outline map up to altering, adding or removing borders, islands and the like. For this reason editable maps are almost universally relatively raster graphics (though in principle a suitable vector source map could be used in a similar way). The second are source maps- where the base-map is used as a template from which to trace geographical features such as coastlines and borders. While technically these are also almost always raster images (including raster exports of vector images) they are usually bitmap or jpeg images with significant detail, and so would require pixel by pixel editing for the production of anything beyond a draft or sketch map.
Finding editable maps
While they sound simpler, editable maps are paradoxically the more difficult to find for one simple reason: the prevalence of .jpeg formats over .png in most online maps. A simple image search for 'blank map of x' or 'outline map of x', where x is in substituted for any modern country, demonstrates the issue. The results you get will be a wide array of black and white examples depicting coastlines, national and subnational borders which will appear to be easy to edit. However, upon using the fill tool in a programme such as MSPaint you'll frequently observe a characteristic 'halo' effect around the borders where jpeg artefacts require filling in individually. This can be worked around in a programme such as Paint.NET by increasing the 'hardness' percentage until these are also filled in, it proposes additional difficulties for the creation process.
Fear not, easily editable outline maps- and indeed historical period maps- have been produced by members of the online alternate history community. Finding these can be something of a challenge, involving searching through forum threads, personal blogs and websites, DeviantArt accounts and social media sites. Some attempts over the years have been made at creating greater organisation, but these are few and frequently out of date.
The somewhat unhelpful, but most useful advice I can possibly give is simply to ask others for help, and there are many on the Sea Lion Press Forum, who can provide assistance, or at least a starting point.
Finding non-editable/Traceable maps
Traceable maps are much easier to find online. Online image searches here can be of more assistance, as a relatively general search- such as 'map of x' or 'map of xth Century y' can produce a wide variety of potential options to use. As a general rule, however, the more recent the period of interest, and the wider the field of search, the more likely you are to get useful results. Thus a search for maps of Czechoslovakia in the 1970s produces a great variety of maps, whereas a search for maps of 14th Century Tibet produces mostly 'false' results in the form of modern maps.
Thus the best place to look is for traceable maps- and especially high quality, large and detailed ones- is often in existing online repositories. A search for 'old maps of x' will usually supply at least a few such sites, and oldmapsonline.org offers a significant variety. Others you will stumble across on your searches, and it's fair to say that the cartographer's favourites list tends to be lengthy, and only ever increases in length. It can also be worth searching the websites of academic institutions, though many of the best resources can require a JSTOR account.
In my personal experience, one of the best repositories is the David Rumsey Map Collection. It has a very extensive collection, and easy to use search function and is frequently updated with new material. The drive to upload whole atlases and providing the option to search by the original publisher also mean that finding one map can be a gateway to finding similar maps of other areas, the usefulness of which cannot be overstated. All of their maps can also be downloaded free of charge in a variety of file sizes.
Avoid worldhistorymaps.info like the plague however. Even if the decade since the website was last updated hadn't seen great strides in the alternate history community to produce more and better maps, it can be taken as a general rule that the more knowledgeable you are about the period depicted in anyone map on that site, the more mistakes you'll see. Some, such as the overuse of 'hard' borders in periods before this isn't applicable, or the overly generous or angular borders in some more sparsely populated areas are more forgivable and suggest the option of a useful starting point. Others- such as including nations and peoples centuries after they had ceased to exist in a meaningful state, or labelling the 12th Century Spanish Kingdom of Leon as a Germanic nation- are significantly more problematic. This is not by any means the only site to be more problematic than useful, but it's fast become one of the more notorious.
The internet, unfortunately, is replete with inaccurate maps- to say nothing of when an image search for historical maps ends up returning alternate history maps instead- and this might lead you to consider alternative options. Even in 2019, historical atlases and textbooks can be extremely useful- especially with the relative ease with scanning images onto a computer that now exists. Taking photographs of posters, maps from books and maps you see out and about- when safe and legal to do so of course- can end up providing some unusual and interesting opportunities, and beyond that there's the option of tracing from satellite images and online map services. It is to the subject of tracing that I shall turn to in the next article.