One of the greatest pleasures of writing fiction must surely be letting our imaginations take flight as we create worlds in which we are in charge and our characters do as we say – to a certain extent, anyway.

But it’s always worth remembering that our fictional worlds still need to be believable in the contexts of our stories, and they still need to reflect the values most of us tend to hold today.

This is probably straightforward enough if we’re writing stories set in our own lifetimes, in the real world and in places we know well.. So historical novelists writing in the 21st century always need to strike a balance between historical authenticity and present-day sensibilities. The Viking hero of a novel written for today’s readership, for example, probably shouldn’t go in for the wanton raping, pillaging and destruction that the historical Vikings who terrified much of Europe during the Dark Ages apparently did. Anyone who remembers the late Magnus Magnusson’s television series about the Vikings will probably recall that in spite of their undoubted prowess as warriors, and their great artistic and navigational achievements, those Norsemen seem to have been a particularly vicious lot, even for the time.