Contained within this letter is a summary of my investigations into the missing kingdom; a more detailed report will follow upon my return to court. Regrettably, even after a search of several months, I have failed to discover any physical traces of the missing kingdom. All that remains is an almost impassable thicket of bramble and thorns. While the notion of magic is implausible, I cannot offer any other explanation as to how an entire realm and its people could have vanished overnight.
Though I did not manage to find anyone hailing from the lost kingdom, I did encounter a few merchants that claimed to have visited that land. Though traders have a tendency to spin a yarn and embellish their tales, I was eventually able to piece together an element common to their stories. In the years before the kingdom's sudden disappearance, there was a sudden and great increase in demand for thread and yarn of all types. At the same time, imports of spindles and spinning wheels were forbidden, and any such device found smuggled into the kingdom was immediately burned on sight.
I surmise that there was some element of madness to the rulers of the kingdom; what else would drive them to deprive their people? In the long run, this would certainly have driven their realm to ruin. But overnight? That requires a malice that is more intentional. Indeed, that suits the information that we already have on hand.
It was recorded in the log of our diplomats that sixteen years ago, a great banquet was held in the vanished kingdom to celebrate the christening of a newborn princess. The log notes that six seats were intentionally left empty at the banquet table, yet no noble or diplomat was absent. At first glance, this could simply be a contingency for the odd forgotten guest. Those more attuned to the customs of the other lands would quickly realize that there never was any forgotten guest; those six seats were reserved for six other pagan spirits.
My most educated speculation is that these pagan spirits are to blame of the disappearance of the kingdom. Perhaps they were spurred into action by some dark ritual of a maddening king. Whatever it is, the truth might never come to light. What is clear is that there seems to be little benefit to further investigations into this matter; my fear is that we would provoke the same forces if we are to continue with our inquiry. In any case, there is no urgent and pressing need to survey the area. While our own nation is always in need for more territory, at our current rates of expansion I expect it would take about a hundred years before such a survey is necessary.