[1] Vandersteen drew inspiration from the main characters in a 19th-century play written by Benjamin Antier and Fréderick Lémaître and from the novels of the same name by Koen Ravestein.

During the late 1980s, early 1990s, with illustrator Ronald van Riet and scriptwriter Marck Meul, Robert and Bertrand were back in their country of origin: France, with drawings in an Art Nouveau style.

[4] Although the historical events in the stories are fairly correctly depicted - as mentioned, the Battle of Solferino - elements do pop up that do not belong in the chosen era.

Other anachronisms aim for a humorous effect - a cameo by a young Eddy Merckx or the reference to the book Bartje, which "has yet to be written".

From 1985 Vandersteen concentrated more on "De Geuzen", and illustrator Ron Van Riet took over the series, with scripts by Marck Meul (with the exception of album 72 and 74 by author Jacques Bakker).