Anna Cathrine of Schleswig-Holstein (10 August, 1618-20 August, 1633) was a daughter of Christian IV of Denmark and his second wife, Kirsten Munk. As this was a morganatic marriage, Anne Cathrine was not considered a princess of Denmark in her life-time. She died at the age of 15. Aside from these details, little information about her life is readily available in English.
↑This appears to be a historical event. She was to be married to a Frands or Frantz Rantzau, who drowned in November of 1632.
↑The first chapters of 1636: Commander Cantrell in the West Indies, which take place in April 1635, mention them as being married, and imply that it was some months ago. However, it could not have happened before October 1634, because Eddie was known to have been involved in moving the guns salvaged from SSIM Monitor.