The Blumenthal family is a Lutheran and Roman Catholic German noble family, originally from Brandenburg-Prussia. Other (unrelated) families of this name exist in Switzerland and formerly in Russia, and many unrelated families (quite a few of them Jewish) called Blumenthal, without "von", are to be found worldwide.
The family was already noble from earliest times (Uradel), dating from the days of the Holy Roman Empire in the Middle Ages, long before the creation of the Kingdom of Prussia and the German Empire, and different branches acquired different titles over time. All living members of the noble family are descended from Heinrich (V) von Blumenthal (1654–93), whose baronial status was limited to the borders of Brandenburg. Other members of the family were raised to allodial baronies (Freiherren), all of which are now extinct, or to countships, of which only one line survives. One member of the family, Georg (I) was a Prince-Bishop (i.e. a head of state). In the case of another, Leonhard (I) the Kaiser announced in the Court Circular his intention to raise him to Prince, but he died months later before this could be enacted.
Like the von Grabow family, whose descendants have included Pushkin, the Blumenthals were originally a branch of the Ammendorf (or Amendorf ) family, who inherited the estates of Blumenthal and Grabow from the only daughter and heiress of Nikolaus von Blumenthal, first referred to in a document of 1240. His family probably originally came from Bloemendaal ("Flower Valley" or "Valley of Flowers") in Holland and re-located first to Blumenthal near Verden in the diocese of Bremen and thence to Blumenthal in the Archdiocese of Magdeburg, where they were vassals of the Wendish Counts of Plotho, naming each settlement after the previous one.
The Plotho family expanded its estates in the Prignitz in the 13th century, bringing Nikolaus von Blumenthal with them. There he named the villages of Blumenthal and Grabow after his properties in the Archdiocese of Magdeburg. The family of his son-in-law, Ruthger von Amendorf, had also come from the country around Bremen. They inherited Nikolaus von Blumenthal's estates and took his name. The castle of Horst, near Blumenthal in the Prignitz, was the family seat for over 600 years, until 1810. The family also claimed a legendary descent from the Roman Emperor Florianus, as well as from the Arthurian knights Garel and Daniel von Blumenthal, whose stories are told in 13th-century poems by Der Pleier and Der Stricker, respectively.
The family had a strong military tradition. Twenty of its members died in battle, including one leading a cavalry charge at Blenheim; eleven fought at the Battle of Königgrätz alone, and of eighteen who served in the Franco-Prussian War eleven fought at the Battle of Gravelotte. Nineteen served in the First World War. Three of its members won the Pour le Mérite (Blue Max), two received the Order of the Black Eagle, one became a field-marshal and six became generals, besides numerous family members who were regimental colonels. The family also produced three Prussian ministers of war, one leading statesman under King Jérome of Westphalia (a Chevalier of the Légion d'honneur), Danzig's longest-serving governor and a prominent 19th-century Bavarian politician opposed to rising antisemitism. One member of the family became a head of state (Georg, Prince-Bishop of Ratzeburg, see below).
All living members of the family are descended from Eustachius von Blumenthal and Margarethe Gans zu Puttlitz (married circa 1575). She was a descendant, via the families of Gleichen zu Tonna and Querfurt from Henry I the Child, Landgrave of Hesse, and thus also of St. Elizabeth of Hungary, St Ludwig of Thuringia ("Ludwig the Holy"), St. Hedwig of Silesia and Charlemagne, besides St. Olga of Pleskau, St. Vladimir of Kiev, St. Ludmilla of Bohemia, St. Olaf of Norway and St. Matilda von Ringelsheim.