For more new books about royalty see:

AUSTRIA/GERMANY/POLAND
Author: Kathrin Dorothea Paszek.
Title: In den Augen der Anderen. Die Wahrnehmung von Jan III. Sobieski in den Korrespondenzen von Habsburg und Hohenzollern (In the Eyes of Others. The Perception of Jan III Sobieski in the Correspondence of the Habsburgs and Hohenzollerns).
Publication: 8 August 2022 by Brill Österreich GmbH.
Language: German.

GERMANY (Sachsen-Gotha-Altenburg)
Author: Stiftung Schloss Friedenstein Gotha, Friedegund Freitag.
Title: Luxus, Kunst & Phantasie. Herzog August von Sachsen-Gotha-Altenburg als Sammler (Luxury, Art & Fantasy. Duke August of Saxe-Gotha-Altenburg as a collector).
Publication: 14 August 2022 by Sandstein Kommunikation.
Language: German.

RUSSIA
Author: Rob Hartmans.
Title: De Tsaar in Zaandam. Peter de Grotes eerste reis naar Nederland (The Tsar in Zaandam. Peter the Great’s first journey to the Netherlands).
Publication: 16 August 2022 by Omniboek.
Language: English.

THE NETHERLANDS
Author: Maarten-Jan Dongelmans.
Title: Oranjeprinses op drift. Wilhelmina van Pruisen en de Nederlanders (Orange Princess adrift. Wilhelmina of Prussia and the Dutch).
Publication: 24 August 2022 by Walburg Pers.
Language: Dutch.

UNITED KINGDOM/FRANCE
Author: Leanda de Lisle.
Title: Henrietta Maria. Conspirator, Warrior, Phoenix Queen.
Publication: 4 August 2022 by Chatto & Windus.
Language: English.