My favourite biography of my problematic stupor mundi fave is unfortunately an older one from 1976, this one, but it is still available.

Renaissance: Kauf dir einen Kaiser by Günter Ogger, about the Fugger merchant dynasty (heavy emphasis on Jakob the Rich and his nephew Anton), is absolutely fascinating, but also old enough not to be on kindle.

Available as an ebook: Madame sein ist eine elendes Handwerk - Liselotte von der Pfalz by Dirk van der Cruyse. Has the downside of Liselotte's baroque German, but has connecting texts in modern German (basically a biography with lots of letters).

Online via Gutenberg: Genie und Charakter from 1924 by Emil Ludwig. Ludwig was the other bestselling biographie romancee writer of the early 20th century, Stefan Zweig's arch nemesis, and this was his attempt to write something like "Sternstunden der Menschheit" - twenty shorty portraits. The first one is of Fritz, later ones include Voltaire, Bismarck, Goethe & Schiller, Leonardo da Vinci, Byron, Rembrandt etc, also colonialists Carl Peters and Cecil Rhodes, and assassinated-by-Nazis minister Walter Rathenau (the most recently dead). Ludwig started out as an ardent national minded conservative (you can tell in his 1914 Fritz drama, which I've also read), became pro democracy through the shock of WWI, saw the Nazis for the scum they were from the start, emigrated when the Nazis came to power, and post WWII ended up on the other end of the ideological scale from where he started, declaring Germans were irredeemable and it should be the Morgenthau plan and also no more Wagner performances ever. "Genie und Character" is him transitioning, so you get emphatic language and admiration for male genius while also psychologizing. The Bismarck portrait contains the gem that Bismarck's idea of being a monarchist did include telling the Hohenzollern, repeatedly, that the Bismarcks had been in the Mark Brandenburg way longer than they had. Märkischer Uradel! Given the Bismarcks and the Kattes being related, I now wonder whether Katte ever teased Fritz with that. The Rhodes and Peters portraits among other things illustrate how you can write about two first degree colonialist exploiters without mentioning black people. At all. The Fritz and Voltaire portraits hold up reasonably well, minus the part where Ludwig, writing in 1924, had no idea about Voltaire/Madame Denis and thus buys that Voltaire just couldn't get it up anymore and that's why Émilie had over lovers.

Stefan Zweig: Die Welt von Gestern. Should be available in any format. These are his memoirs of his pre WWI youth in Vienna, written in 1942 shortly before his suicide, and they still count as one of the best portraits of Austrian, specifically Viennese society - as seen from a young Austrian-Jewish intellectual - of the era, the Habsburg world in its twilight years, and the Vienna that produced both Freud and Hitler and was irrevocably destroyed by the later.

I have one more ebook rec, which I'll mail to you since I can't give it here.