One of the most daunting things about research on the crusading movement in the Baltic is the linguistic demand of the material. The primary sources are composed mainly in Latin, and this is true for the legal and narrative material. This is not really a challenge to the medievalist of today (although it seems less and less students are taking Latin anymore). Alongside Latin, though, working on the Teutonic Order means that researchers need to be familiar with Middle High German (MHG; Mittelhochdeutsch), which is essentially what the German language looked like from 1100-1500. MHG sources are rich in terms of their literary value, and it's a pretty fun task for the historian to go about translating texts written in rhyming couplets (which most of the Order's chronicles in MHG are). This is all, of course, in the framework of a really difficult body of material in modern languages (have you ever tried reading academic Polish or German?!)
MHG is not something that is commonly taught in English-speaking graduate programs (at least to the best of my knowledge). During the course of my research into the Baltic Crusades I was fortunate enough to get my introduction to the topic with Mary Fischer's 2010 translation of Nikolaus von Jeroschin's Chronik von Pruzinlant (the Chronicle of Prussia), written sometime around 1341. In addition to this, there are only three other sources translated into English that deal exclusively with the Baltic crusades: Henry of Livonia's Chronicon Lyvoniae (the Chronicle of Livonia) and an anonymous MHG chronicle, the Livlaendische Reimchronik (the Livonian Rhymed Chronicle). While these are invaluable to researchers on the Baltic crusades, there remains a massive body of material that is not translated to English. During the course of my PhD research I noticed how valuable translations could be (mostly because I've had to do my own!), especially given the significant amount of scholarship coming out in English on the Baltic crusades in the last 20 or so years. So, one of my projects is producing more English translations of important Teutonic Order sources.This is quite a fun project because it involves familiarizing myself with material that mostly gets overlooked in circles outside of Germany or Poland. It's amazing the amount of material that is still out there in older, edited collections. So far, I've translated two letter-like accounts written in the 1250s and the 1350s respectively, both in MHG.
The first was edited in 1876 by the great German historian, Theodor Hirsch, in the fifth volume of Scriptores rerum Prussicarum. He gave it the title 'Hermann von Salza's Bericht ueber die Eroberung Preussens' (Hermann von Salza's Report on the Conquest of Prussia). It's quite a small source, only 10 pages, but it is in fact the earliest record of the Order's conquests in the Southern Baltic. I translated the entire thing during the course of my PhD and it was really eye-opening in terms of how useful it could be to researchers. So, I'm currently preparing that translation as a journal article, where it can be used by researchers studying the crusading movement in Northeastern Europe. The second is a letter written around 1350, and is a report of the Battle of the Streba (1348). It was edited by the great Prussian historian, Johannes Voigt, in his Codex diplomaticus Prussicus (vol. 3, 1848). The letter is a useful tool for looking at crusade ideology in the Baltic in the 14th century, since it frames the battle in highly religious terms and even includes some in-depth biblical citations. This is something that (to my knowledge) is quite rare in the Order's vernacular literature (outside of chronicles and translations of biblical books, of course). The letter is also important because it allows us to look at questions of group identity, religious understanding, and memory, after nearly 100 years of holy war in the Baltic. How does it reflect the view of crusading after the Fall of Acre and the end of the 'traditional' (whatever that means) crusades in the East? Moreover, what does this small letter say about the Order's perception of itself as a religious institution (outside of the well-known chronicles produced in the 1320s, etc.)? Providing a translation and commentary answering those questions is currently what I am doing at the moment, and would make for a useful tool to researchers on the later crusading movement.