Estonia
The northern-most of the three Baltic states (Latvia and Lithuania are the other two to the south), which share a significant part of modern history: after a brief period of independence in the inter-war years, the country was (re-)occupied during WWII by the Soviet Union (on the basis of the Molotov-Ribbentrop Pact) in 1940, and then by Nazi Germany, after the latter invaded the USSR (Operation Barbarossa) in June 1941.
After the Germans had been kicked out by the Red Army in late 1944, Estonia became incorporated into the Soviet Union again until the country regained its independence in 1991 during the unique "Singing Revolution". The latter term makes reference to the defiant singing of traditional songs and hymns in Estonian, which under Soviet rule was forbidden, at rallies and nationwide demonstrations from the late 1980s onwards. Not surprisingly, then, Estonians are proud of their traditions and songs and the role this played in ending communist repression. This is covered in a specialist museum in the capital Tallinn, which is also the location of most other places of relevance to the dark tourist, except one that is to be found in the south-eastern second city of Estonia, Tartu.
Travel to Estonia is these days very easy, with good air, land and sea connections (see under Tallinn), in fact Tallinn at least has become a very popular city destination both for Westerners and for people from other former Soviet republics, in particular Russia.
However, there remain frictions with the country's large ethnic Russian community,which accounts for about 25% of the population. These people were kind of left in limbo and virtually stateless when Estonia regained its independence in 1991, as only citizens who can speak Estonian were granted an Estonian passport. Given that Estonian is a language not related to any Indo-European languages, including Russian, but instead is part of the isolated Finno-Ugric family (whose other members are Finnish and Hungarian), it was perceived as an unfairly difficult hurdle for non-Estonian former USSR citizens in the country (in 1992 still almost a third of the population!). The regulations have been somewhat relaxed, but there is still quite a proportion of minorities (mostly Russians) in Estonia without full citizenship (ca. 7-8%).
In addition, the Soviet past and the concomitant association with Russia are these days very much resented by Estonians, who much rather look to the west and see themselves as Europeans, closer linked to Scandinavia than to their Slavic neighbours in the east. Communism is almost a dirty word these days and all memories of the Soviet era are generally suppressed.
This has repercussions for dark tourism. Relics of the Cold War and Soviet Union form the main attraction of Estonia for dark tourism but this is not really officially endorsed. There are various offers in the private sector, though, that make up for that lack of official recognition. So you can now see KGB exhibitions, a former Soviet prison, various left-over Soviet-era memorials (though many are in a bad state of neglect) and so on.
The other dark chapter in Estonia's 20th century history, the occupation by Nazi Germany in WWII, has left far less sites for dark tourists to visit today. Unlike Latvia and Lithuania, Estonia did not have a sizeable Jewish population , so when the Holocaust came with the Nazis, it did not have the absolute scale it had in the other two Baltic states or Poland and Belarus. In relative terms, however, the Holocaust in Estonia was absolute. This is documented in the most sinister way on that infamous map drawn by the commander of the Einsatzgruppe A, Franz Walter Stahlecker: figures next to little drawings of coffins recorded the relative numbers of Jews murdered in the countries of Eastern Europe by October 1941 – and next to the number “963” for Estonia the word "judenfrei" is written (literally 'free from Jews'), i.e. it reported that the extermination of the Estonian Jews had been achieved 100%! (This was specially acknowledged at the Wannsee Conference.) A copy of this map is a common exhibit in many Holocaust museums. However, probably because the absolute numbers weren't as horrifically huge as in those other countries, Estonia lacks any dedicated Holocaust museums or large memorials such as you find in Riga, Liepaja, Vilnius or in Poland.
So the two historically most significant and darkest chapters in Estonian history are quite under-represented in the country's tourism portfolio.
Estonia is much happier in promoting its medieval history, its nature, singing and other elements of its idiosyncratic culture. Fair enough. There is no denying these things offer a lot of appeal to tourism in general. But for dark tourism sites, one has to dig a little bit deeper. I hope these pages will help. Publications such as the In-Your-Pocket guides are also a very good resource, as is the Baltic Network Cold War website (coldwarsites.net).