| Claus-Casimir van Oranje-Nassau van Amsberg | |
| Count of Oranje-Nassau, Jonkheer van Amsberg | |
| Full Name: | Claus-Casimir Bernhard Marius Max van Oranje-Nassau van Amsberg |
| Birth Date: | 21 March 2004 |
| Birth Place: | HMC Bronovo, The Hague, Netherlands |
| Royal House: | Orange-Nassau |
| Father: | Prince Constantijn of the Netherlands |
| Mother: | Laurentien Brinkhorst |
| Religion: | Protestant Church in the Netherlands |
Count Claus-Casimir of Orange-Nassau, Jonkheer van Amsberg (Claus-Casimir Bernhard Marius Max; born 21 March 2004), is the second child of Prince Constantijn and Princess Laurentien of the Netherlands[1] and their only son. He is a member of the Dutch royal family and is sixth in the line of succession to the Dutch throne.[2]
His birth was overshadowed by the death, only a day before, of his great-grandmother Queen Juliana.[3] He has two sisters: Countess Eloise, born 8 June 2002 and Countess Leonore, born 3 June 2006.
His baptism took place in the chapel of Het Loo Palace in Apeldoorn on 10 October 2004.[4] Claus-Casimir's godparents are King Willem-Alexander, Prince Maurits of Orange-Nassau, van Vollenhoven, Ed P. Spanjaard, and Countess Tatiana Razumovsky von Wigstein.
After studying at Vrijzinnig Christelijk Lyceum (VCL) in The Hague, Claus-Casimir moved to Scotland to attend Gordonstoun School where he graduated in June 2022. Since September 2022, he studies at ESCP Business School. He studied the first year in Paris and he is currently studying the second year in Turin.
By royal decree of 11 May 2001, nr. 227, it was determined that all children and male-line descendants of Prince Constantijn of the Netherlands would bear the title of Count (ess) of Orange-Nassau (with princely rank) and the honorific Jonkheer (Jonkvrouwe) van Amsberg with the style of "His/Her Highborn Lord/Lady" and have the surname Van Oranje-Nassau van Amsberg.
Upon the abdication of Queen Beatrix on 30 April 2013, the children of Prince Constantijn and Princess Laurentien ceased to be members of the Royal House, although they continue to be members of the royal family.[5]