And as I suspicioned: Geoffrey Trease happened to start writing in a period (the 1930s) which seems to have been very pro Royalist (an allegory with Spain perhaps?).
In the 1940s the two pro-Royalist books are by Jane Lane, the two pro-Parliament books are by Geoffrey Trease.
I've finally started writing and if I get the chapter sketched by Monday I'll be asking for Beta readers.
