The term ‘Byzantine’ was not coined until the sixteenth century. In fact, those we have come to know as the Byzantines called themselves Romans, or ‘Rhōmaioi’ to use the Greek. The Eastern Roman Empire centred on Constantinople was the direct successor to the empire centred on Rome and survived for over a thousand years: from the last centuries of antiquity well into the High Medieval Period, at last falling in AD 1453. Complicating matters, the Romans ceased to use Latin as their primary language (particularly of law and administration) in the late sixth century, so by the early eighth century – the setting of this novel – both the common tongue and the official language of the empire was Greek. It seemed to me that to use the term ‘Roman’ risked evoking the wrong epoch and could be confusing for any reader not already familiar with this period of history. Hence my use of ‘Byzantine’.

Coupled with this, I felt it was clearer to refer to the Imperial City as Byzantium and not Constantinople throughout. Byzantium is easier to read (and to write!) and created the link with the name I was using for its inhabitants. Thus, although my pedant nerve was twitching violently all the way, this is the choice I made. In any case, Constantinople has had many names: the City, the Great City, the Queen of Cities, the Imperial City, the Mother of Cities, New Rome, Second Rome, Miklagard (the Norse name for it, which translates simply as ‘Big City’), in time Stambul; and finally Istanbul.

The Arabs, too, might have been called several other names: Saracens, Muslims, Syrians, Ishmaelites, Mohammedans, and more. I went with ‘Arabs’ simply because as a collective noun it seemed to best encompass the actual people involved.

Unusual though Erlan and his friends’ presence in Constantinople was at this date, by around a hundred and fifty years later Norsemen and women would become commonplace there. In particular, those Scandinavians serving as the famous Varangian Guard. (So-named because in their early days they swore an oath of allegiance to the emperor on the name of Vár, the Norse goddess of oaths and agreements.)