Borderlines explores the global map, one line at a time.

June 13th, 1990, was a historic day for weather forecasting in Germany. For the very first time, the weather map on the Tagesschau [1] showed the newly reunited country’s international borders.

Before, German meteorologists made do with merely topographical maps of a borderless Europe. This was to keep ideology out of meteorology: showing (or not showing) the border between East and West Germany would have meant acknowledging (or denying) that this too was an international border.

Now defunct by just over two decades, the border between the two Germanys already seems like a surreal relic from a much more distant past. Was there really ever a 540-mile Strip of Death separating the two halves, from the Czech border to the Bay of Lübeck? There was – and it was quite hermetical, and very deadly [2] – but today a visitor might be forgiven for thinking otherwise.

Joe Burgess/The New York Times

These days, the so-called innerdeutsche Grenze is almost completely erased from the landscape, marked only by the occasional memorial placard along the Autobahn. The fences, the spotlights, the guard dogs and the tanks have all been withdrawn. But that doesn’t mean it’s gone. The line that separated the Federal Republic of (West) Germany from the (East) German Democratic Republic is a zombie border: it’s been dead a few times in the past, and that hasn’t stopped it coming back. The line between east and west existed long before the postwar split.

The German part of what was called the Iron Curtain started on the Czech border at an old tripoint between the ancient kingdoms of Saxony, Bavaria and Bohemia [3]. On its northward course it largely followed the borders of German princely states as they had existed since the Middle Ages.

Admittedly, the view is complicated by the proliferation of small states so typical for pre-unification Germany, but squint at a map of the Holy Roman Empire [4] in its latter centuries, and you’ll see the 20th-century intra-German border prefigured. It’s right there, at the western edge of Thuringia, Magdeburg, the Altmark and Mecklenburg-Schwerin.

But why? After flattening much of Germany, why would the Allies pay any heed to medieval demarcations when occupying it? The border between FRG and GDR started out as the line where the Soviet zone of occupation in the east met the British and American zones. Not only did the Soviets have a bone to pick with Germany, but communism itself seems antithetical to the feudalism that shaped those borders.

The answer is, most likely: convenience. Many if not most “new” international borders, which we take to be the result of recent politics, are in fact older, subnational ones. Drawing completely new borders means having to negotiate and compromise, exchanging territorial tit-for-tats. Plus, by taking over old administrative units in their entirety, you’re inheriting an established capital with a centralized administration that has a reach covering the entire territory. Relying on old borders, already familiar to the locals, saves the occupier a lot of bother.

But there is an even deeper historical layer to Germany’s East-West divide. If the 20th-century border was ideological, and the 18th-century one dynastic, the separation in the Early Middle Ages was ethnic. Almost exactly a millennium before Stalin staked his claim to East Germany, a weirdly similar border divided the East Francian kingdom of Henry I the Fowler, first king of all Germans (919-936) from the Slavic lands in the east.

Around that time, most of what became the German Democratic Republic was settled by Slavs. Indeed, the Slavic history of what is now eastern Germany has been caught in the amber of its toponymy: Any town name ending in -ow (Treptow), -au (Spandau) or -itz (Chemnitz) most likely has a Slavic root. Even Berlin refers back to “berl,” ancient Slavonic for “swamp” (near which the original settlement was built), and not to Bär, German for the bear that really has no business gracing the city flag [5].

Henry founded the powerful Ottonian dynasty – his son Otto would be the first German emperor – and started the tradition of German eastward expansion. In the centuries up to the world wars of the 20th century, German conquest, settlement and acculturation had pushed back the Slavosphere hundreds of miles. Even today, pockets of ethnic Slavs still exist within German borders, most notably the Sorbs, who live in and around the Spreewald marshlands southeast of Berlin and speak a language closely related to Polish. Hitler explicitly placed his quest for more Lebensraum in the east in the tradition of that Drang nach Osten [6]; he even sent German anthropologists into Poland and Russia to find evidence that ethnic Germans had once occupied those territories.

Stalin, too, saw the contemporary conflict with Germany in a millennial context. In his victory speech to the people on May 9, 1945, he said: “The age-long struggle of the Slavonic peoples for their existence and independence has ended in victory over the German aggressors and German tyranny.”

This might explain why the Soviets were the first of the Allied quartet to propose the borders of their occupation zone [7] – they had studied their historical atlases beforehand, and were determined to roll back German eastward expansion from its high-water mark at the gates of Moscow to its earliest beginnings, on the banks of the Elbe. As the Swiss historian Walther Hofer wrote, “The Third Reich did not turn out to be a thousand-year empire, but in the twelve years of its existence, it managed to undo the historical achievement of a thousand years” [8].

But this was hardly the end of things: the Red Army’s advance to the Elbe, once indeed the border between Germanic and Slavic tribes, turned out to be the Soviet Union’s own high-water mark. By 1990, state communism had retreated from Central Europe. In a dramatic reversal of fortune, the Soviet Union was about to collapse as Germany’s two halves re-unified [9].

The Iron Curtain that divided Europe (and Germany) is gone. The European Union now includes much of Eastern Europe, and indeed some bits of the former Soviet Union. In Angela Merkel, Germany has its first chancellor raised in the former East Germany. Although many socio-economic indicators for the ex-GDR are still not up to par with the western half of Germany, the border itself has been thoroughly erased from the landscape.

So is that the end of Henry the Fowler’s thousand-year-old border? Maybe not. Erased borders are like phantom limbs – sometimes it feels like they’re still there, even when they’re manifestly not.

For one of the most remarkable examples of this revenant quality of former borders, we need only hop across the Oder-Neisse line to Poland. On the map of post-communist Poland’s election results, one curious division keeps cropping up: the old imperial border between Russia and Prussia/Germany, as it existed when Poland did not, from 1848 to 1918.

In the electoral districts west of that border, it’s usually the more liberal candidates and parties that win a majority. To the east, with the notable exception of Warsaw, the more conservative ones mostly carry the day. This map shows the geographic distribution of majorities in the first round of the most recent presidential elections, in 2010, pitting Bronisław Komorowski (candidate for the liberal Civic Platform party) against Jarosław Kaczynski (candidate of the conservative Law and Justice party). Mr. Komorowski, who defeated his opponent 53 percent to 47 percent, won majorities mainly in the formerly Prussian part of the country, with Mr. Kaczynski winning mainly in the formerly Russian part.

Related More From Borderlines Read previous contributions to this series.

The fit between modern election result and ancient border is almost perfect. But how can this be? The ethnic composition of the region has been shaken up thoroughly since the border last was in effect: following the Second World War, Germans were expelled from areas east of the Oder-Neisse line, and Poles moved in from former Polish areas to the east, now annexed by the Soviet Union.

Yet in spite of these completely different demographics, the former border keeps resurfacing at Polish national elections – a zombie border indeed. Earlier treatment of this question [10] has offered up a few intriguing hypotheses: The resettled Poles haven’t had the time yet to “get conservative”; the newer Polish areas have richer farmland (or a denser rail network), are thus more likely to have liberal politics. But an answer that fits the question as snugly as the old border fits contemporary election results remains elusive.

It may seem overly deterministic to link modern election results to ancient borders that no longer exist; but similar claims have been made about election outcomes in France, Ukraine and the United States, to name but a few countries.

The Web site Electoral Geography is an excellent place to lose a few hours looking for evidence of old borders, or any other social patterns, in election result maps. And when all those shifting boundaries get a bit too much for you, maybe it’s finally time for the Tagesschau’s soothing weather map, where the only lines moving across Europe are the cold fronts.

Frank Jacobs is a London-based author and blogger. He writes about cartography, but only the interesting bits.

[1] The daily news show on Germany’s first public TV channel ARD (Das Erste, as opposed to the second public TV channel ZDF, das Zweite).

[2] At its height, the border (not counting Berlin) was secured by an overlapping system of 273 miles of spring-gun installations, 143 miles of minefields, 374 miles of ditches (to prevent vehicular evasion) and 434 observation towers. Bordering the 30-foot-wide Strip of Death (“Todesstreifen”) was a 1,500-foot-wide Control Strip (“Kontrollstreifen”) and a nearly three-mile-wide Exclusion Zone (“Sperrzone”) with limited access for non-residents. Between 1948 and 1989, 560 people were killed while attempting to cross this border without permission (in Berlin, the total body count was around 250).

[3] Before 1989, that would have been East Germany, West Germany and Czechoslovakia, respectively. The tripoint is located at the very tip of the so-called Aš Panhandle.

[4] A long-lived (962-1806) but weak union of mainly German states, presided over by an emperor chosen by a college of prince-electors (“Kurfürste”). Voltaire famously dubbed it “neither Holy, nor Roman, nor an Empire.”

[5] See also Oswald Jannermann, “Slawische Orts- und Gewässernamen in Deutschland, von Belgard in Pommern bis Zicker auf Rügen.”

[6] And not just Hitler. The SS Chief Heinrich Himmler laid wreaths at the grave of Henry I the Fowler, and may have believed he was his namesake’s reincarnation.

[7] On May 12 1944, four months before the United States, Britain and France had even thought about delineating their zones.

[8] Walther Hofer, “Der Nationalsozialismus. Dokumente 1933–1945.”

[9] Prompting many Europeans to share the sentiment expressed by then-Italian prime minister Giulio Andreotti: “We love Germany so much that we would prefer to have two of them.” (Andreotti was quoting the French writer François Mauriac).

[10] See Strange Maps No. 348.