A trained annalist, his research for each novel has been rigorous.
From the guardian.co.uk
The annalist structure is followed strictly, to the extent of listing the four seasons of each year even when no events are recorded.
From the en.wikipedia.org
Eusebius'work consists of two books, the Chronographia, a summary of history in annalist form, and the Chronikoi Kanones, tables of years and events.
From the en.wikipedia.org
The anonymous annalist who composed one of the Anglo-Saxon chronicles repeated Bede's list of seven kings in a famous entry under the year 827, with one additional king, Egbert of Wessex.
From the en.wikipedia.org
This work includes material from a copy of the Chronicle, but it is very difficult to tell which version because the annalist was selective about his use of the material.
From the en.wikipedia.org
Annalists were different from historians, in that an annalist was more likely to just record events for reference purposes, rather than offering their own opinions of events.
From the en.wikipedia.org
More examples
A historian who writes annals
(annalistic) relating to annals; "a book with an annalistic approach"
Annalists (from Latin annus, year; hence annales, sc. libri, annual records), is the name given to a class of writers on Roman history, the period of whose literary activity lasted from the time of the Second Punic War to that of Sulla. ...