By: Stephen
C. Neff, Reader in Law – Public International Law, University of Edinburgh Law
School
The frontier in question is not the American wild west –
though it was wild enough in its own way. The reference is to the northeastern
frontier of Latin Christendom in the Middle Ages. It was the scene of one of
the three great crusade enterprises of the period – and the least known of
them. The other two were in the Holy Land in Palestine and Spain. The
northeastern crusade differed from the other two in being directed not against
Muslims, but rather against pagan peoples of Lithuania and other assorted
non-Christian groups, who inhabited lands around the southeastern corner of the
Baltic Sea. These lands boasted of storybook-sounding names such as Livonia,
Courland, Galindia, Samogitia, Varmia, Pogezania and Estonia (the last one
still with us). In Germany itself, a remnant of these populations continues to
exist, in the form of a minority group known as the Sorbs.
Entrusted with the crusade effort was a group known as the
Teutonic Knights. They had been founded as a military order in Palestine in
1198, during the Third Crusade – with the impressive title of the “Order of the
Brothers of the Teutonic House of the Virgin Mary in Jerusalem.” A key event
in their relocation to the Baltic region was the investiture of the Order’s
master as an imperial prince for Kulmerland by Holy Roman Emperor Frederick II,
in the Golden Bull of Rimini in 1226, which gave the Order effective control of
Prussia. In 1234, Pope Gregory IX graciously accepted Prussia as a feudal
fief, to be held by the Order under papal suzerainty. The Knights’ polity was
known at the time as the Ordenstaat, or State of the Teutonic Order.
The Christianity manifested by the Teutonic Knights was of
the decidedly muscular variety. Their campaign against the Lithuanians in
particular was essentially a permanent programme of ethnic cleansing, extending
for over a century. In a series of virtually annual expeditions that began in
the early Fourteenth Century, the native Lithuanian population was driven out
of the area that became East Prussia and replaced by German colonists under the
tutelage of the Order. The resemblance to the American west is not altogether
far-fetched.
Trouble, from the legal standpoint, began in 1386, when
Queen Jadwiga of Poland undertook a rival strategy that could be described –
perhaps with some generosity – as making love rather than war. That is to say,
she married the pagan grand duke of Lithuania, Jogailo, who thereby assumed a
second legal identity as King Wladyslaw II of Poland. An important part of the
arrangement was that Wladyslaw would convert to Christianity, as he duly did.
The Teutonic Knights, however, were not disposed to be deprived, in this abrupt
manner, of one of their foremost raiding targets. They continued to mount
expeditions in and against Lithuania. But the Polish-Lithuanian Kingdom
elected to strike back. They did, with a vengeance, at the Battle of
Tannenberg in 1410, in which a massive defeat was inflicted by the Polish-Lithuanian
side onto the Knights. A peace agreement the following year took the territory
of Samogitia from the Knights, and more importantly subjected them to the
payment of a heavy indemnity (£850,000). Moreover, the Polish-Lithuanian state
continued to mount attacks on the Ordenstaat.
The Knights responded by shifting their effort, at least
temporarily, to the legal sphere. They lodged a complaint with the papacy
against Poland-Lithuania, seeking an order barring the two states from mounting
further attacks against the Knights, and also requesting a reaffirmation of the
Knights’ entitlement to undertake crusading in the region. Part of the Order’s
complaint was an accusation that Poland-Lithuania was employing pagan troops
against the Christian knights. The stage was set for one of the epic legal
confrontations of the European Middle Ages.
The scene of the legal duel was the Council of Constance,
in Switzerland, convened in 1414. This gathering became famous for two other
reasons, unrelated to our present concern. One was the resolution of the Great
Schism, which had been tearing the Catholic Church apart for a generation.
This was achieved by the sweeping away of all existing rival claims to the
papal throne, in favour of a compromise candidate who became Pope Martin V.
The other famous result was the trial and execution of Jan Huss of Bohemia for
heresy – despite his having been given a