That Elisabeth Förster-Nietzsche falsified her brother's letters and other writings was something that several scholars had already been aware of before her death in 1935. This includes scholars such as Heinrich Rickert and Erich Friedrich Podach. The Nietzsche-Archiv founded by Elisabeth Nietzsche supported several editions of the philosopher's work. These include the following:
- An edition by Fritz Koegel comprising eight volumes of works and four volumes of Nietzsches "Nachlass" / literary remains, published in the years 1895 - 1897. In the literature, this edition is identified as GAK ("Gesamtausgabe ed. Koegel"). This edition may be reliable. It was later criticised by Ernst Horneffer of the Nietzsche-Archiv, but this attack may be seen as a tactic to justify a new edition; Rudolf Steiner defended Koegel and exposed Elisabeth Förster-Nietzsche's incompetence with regard to her brother's philosophy.
- The so-called Großoktavausgabe ("big octavo edition", due to its format) in 19 volumes published in the years 1894–1913.
- Several editions of what is known as Der Wille zur Macht / The Will to Power drawn from the philosopher's Nachlass by Elisabeth Förster-Nietzsche and Heinrich Köselitz (1901, 1906, 1911, 1917, 1930).
- An edition published in the years 1895–1904 and known as Kleinoktavausgabe ("small octavo edition").
- Cheap editions of Nietzsche's works during World War I.
- One or more editions by Richard and Max Oehler, who both worked to create an image of Nietzsche's philosophy that conformed to Nazi ideology. These editions include the 20-volume edition published by the Musarion Verlag in Munich in the 1920s and the leather-bound 23-volume edition by Musarion in 1929, which can still be bought from antiquarian bookshops (if your pockets are deep enough; some of the leather-bound volumes are sold for over €3,000).
- The Historisch-Kritische Gesamtausgabe, starting 1933, which was never completed.
Readers who want to avoid editions of Nietzsche's works overseen by Nazi sympathisers should steer clear of any edition that describes itself as "im Auftrag von Elisabeth Förster-Nietzsche veranstaltete Werkausgabe" ("edition arranged on behalf of Elisabeth Förster-Nietzsche") or any edition from the years 1901-1945 that were published on behalf of Elisabeth Förster-Nietzsche or the Nietzsche-Archiv.
Any edition published before 1894, the year of the Nietzsche-Archiv's foundation, would also be free of interference by Nazi sympathisers, but those original editions tend to be unaffordable.
The safest bet is the editions by Giorgio Colli and Mazzino Montinari, starting in the late 1960s. There are several options here, depending on how serious you are about studying Nietzsche's work:
- Werke. Kritische Gesamtausgabe. Edited by Giorgio Colli and Mazzino Montinari. Berlin and New York: De Gruyter, 1967 and later. This contains a very extensive critical apparatus and is not for the general reader (both because of the editorial content and its price). In the literature, this edition is referred to as KGW.
- Sämtliche Werke, Kritische Studienausgabe in 15 Bänden. Edited by Giorgio Colli and Mazzino Montinari. Munich and New York: De Gruyter, 1980. This is a somewhat more affordable edition based on the "Kritische Gesamtausgabe". In the literature, this edition is referred to as KSA.
- Digitale Kritische Gesamtausgabe von Nietzsches Werken und Briefen (eKGWB): digital version of Colli and Montinari's Kritische Gesamtausgabe (KGW).
Since the print editions by De Gruyter are expensive, it is advisable to look for other editions based on the work by Colli and Montinari. For example, the edition of Richard Wagner in Bayreuth. Der Fall Wagner. Nietzsche contra Wagner published by Reclam states that it is based on Colli and Montinari's KSA (Kritische Studienausgabe).
For an alternative to Colli and Montinari's edition, one should look to the volumes edited by Claus-Artur Scheier and published by Meiner in Hamburg since 2013. Meiner is a publisher that specialises in editing and publishing philosophical and theological works. The Nietzsche edition consists of six volumes based on the original editions from the 1880s, i.e. well before Elisabeth Wagner's interference.
When looking for a translation, one should always check which German edition the translation is based on, e.g. texts published before 1894 or (preferably) Colli's and Montinari's edition. (In fact, Colli and Montinari started their edition because they were looking for a reliable starting point for an Italian translation of Nietzsche's work and they couldn't find anything that met their criteria.)