What is the author's tone in Nicholas and Alexandra by Robert K. Massie?

The book is written in the third person with the narrator being the author. The book is written in a straightforward objective matter but it reads like a novel. The facts are presented without much emotion. The author's personal views on the revolution or politics very rarely come across. At no time does the author try to force his views on the reader. His knowledge of hemophilia comes across at different points in the book where he explains different things about the disease or how parents react to the disease and the suffering of the child.