I. Prelude (1409-1411)
The Samogitian Question
As the fog that had shrouded Europe for the better part of a thousand years began to lift before the light of the Renaissance, this bitter region in modern Lithuania remained the last holdout. Clinging stubbornly to their pagan deities and festivals, these hardy people resisted attacks from Masovia, helped their cousin Semigallians decimate the Livonian Brotherhood, and stood up to the Teutonic Order.
The Teutonic Knights, formally the Order of the Teutonic Knights of St. Mary's Hospital in Jerusalem, were established at the end of the twelfth century. In 1230 they migrated to the Baltic to join the series of crusades aimed at converting the region to Christianity. Given a near carte blanche by the Papacy and supported by the Holy Roman Emperor, the Order took in the defeated Livonians and came to hold a strip of land from Pommerania to the Russian states.
Time left the Teutons behind though. In 1242 they lost the Battle of Lake Peipus, ending any aspirations against the Rus. They continued to attack (and antagonize) pagan Lithuania, but in 1387 they finally converted as well. The monastic order was quickly losing its raison d'etre and resembled the secular states around them more and more.
A particularly mean spirited state, if reputation meant anything. Whereas the Lithuanians, despite a century of vacilliating between east and west and playing one against the other, ultimately converted a high percentage of their nobility and peasantry peacefully, the Teutons opted for more direct and brutal tactics. They chose fire and sword, and as almost always happens when a state grows too reliant on fear, the Order was about to pay a terrible price for their infamy.
As the fourteenth century ended, the Order destroyed pirates for Sweden in exchange for Gotland and continued to pressure Lithuania. Intervention in a civil war won them Samogitia. Interestingly, the Knights made no serious effort to convert the population - though raids, arson, murder and all the other crimes that go with warfare continued. The Samogitians revolted in 1404. When Paul von Wattzau came to Samogitia at the head of five hundred heavily armed 'missionaries', they did so again in 1409.
Saving Your Soul by Force
Vytautas (the Great), Grand Duke of Lithuania, announced that he would protect 'his' people against Teuton incursions. It was a flimsy pretext, but it served as Ulrich von Jungingen, Hochmeister (Grand Master) of the Teutonic Order, tersely declared war on the Polish-Lithuanian union in August 1409.
The Polish-Lithuanian War
Von Jungingen expected a two prong assault, with the Poles attacking the rich port city of Danzig while the Lithuanians would attempt to 'liberate' Samogitia and so seperate the Teuton and Livonian Orders. He attempted to drive Poland from the war in the first weeks, but Wladyslaw II repelled the German invasion and retook Bydgoszcz (Bromberg). As the harvest ripened, the Emperor arranged a truce until June 24, 1410.
The next summer the Polish-Lithuanian alliance massed a great army to destroy the crusading threat once and for all. Von Jungingen asked to extend the truce until July 4 to allow more mercenaries to arrive while entrenching the bulk of his army in castles to the east. The alliance screened their intentions with a series of raids and crossed the Vistula River on June 30. Their armies, along with banners from Masovia, Smolensk (under the Lithuanian banner) and Moldavia merged on July 2 and drove towards the Teuton capital of Marienburg.
The Knights were caught off guard, but had not been completely idle. Mercenaries were arriving by the day from German states as well as Western Europe. Von Jungingen amassed his own army and, after some maneuvering, squared off near Tannenberg.
Eyewitness accounts are contradictory, and late medieval scholars were far too generous with their numbers. The Lubeck chronicle numbers the Allied army at nearly 5 million - a ridiculous amount for a single clash of arms even if medieval logistics allowed it. Modern sources give the Teutons approximately 16,000 soldiers, mostly heavy cavalry with a large contingent of 'guests.' The Alliance numbered some 16,000 Polish heavy cavalry, 8,000 Lithuanian light cavalry, and perhaps a few thousand 'guests' of their own.
Everyone agrees the Teutons were badly outnumbered, but few soldiers in Europe were as disciplined as these crusaders. Further, they had the technological edge, having brought several lead shooting bombards to the melee. This may be the first example of cannon being used in eastern Europe - they debuted in the west during the Hundred Years War.
The Battle of Tannenberg took place on July 15, 1410 and was an unqualified disaster for the Knights. The Order's left flank chased retreating Lithuanian cavalry into the swamps where they bogged down while the Lithuanians had time to regroup. The main battle between each side's heavy cavalry proved to be very close, with the Knights gaining the upper edge until Wladyslaw II committed his reserve. This in turn forced von Jungingen, at the head of sixteen banners of soldiers, to charge into the fray.
Unfortunately the false retreat, committing his reserve too early, and betrayal by Nikolaus von Renys, a Polish sympathizer who refused to lead his unit into battle, proved to be too much. The Lithuanians returned to the battle and the now heavily outnumbered Order crumbled before the onslaught. Von Jungingen died and retreat turned into rout. Chroniclers reported more bodies were found at the Teutons' camp than on the battlefield.
What could have been a decisive diplomatic coup, a chance to gain the upper ground and prove God stood with the Polish-Lithuanian alliance, was soon soured by their own peasantry. The 'rules' of warfare prohibited wanton killing, at least of valuable nobility that could be ransomed off. The peasantry didn't stand to gain from these ransoms and had two centuries of fear and anger to avenge. Thousands died including the Grand Komtur, Grand Marshall and other high ranking officers before the nobility could restore order. Those that did survive the carnage were eventually ransomed home along with many of the mercenaries.
Here, though several castles surrendered and a few Baltic towns rose in revolt, the allied host paused. This was a fatal error, as it gave Komtur Heinrich von Plauen time to swing into action. His tough, no nonsense approach rallied the disheartened soldiers coming home. Tales of rampaging pagans incited people desperate to protect their homes, and by the time the host arrived to siege Marienburg he'd made the city difficult, if not impossible, to take.
As summer faded into autumn once more, the restive Polish and Lithuanian nobility wanted to go home before the harvest. They dissolved without taking the capital. For his part, von Plauen's heart and soul was willing to continue the desperate melee, but he knew he needed to rebuild his shattered army and economy. He agreed first to a truce, then to the Peace of Thorn in February 1411.
The Peace of Thorn was the kind of compromise that satisfied no one, angered everyone and yet was probably the best move on the table. The Poles regained the disputed Dobrin Land while Lithuania took back Samogitia. The Order agreed to pay a ransom for the survivors of Tannenberg hefty enough to choke the economy for years to come.
Though the Alliance had reason to believe their Teutonic rivals were done as a crusading threat after losing Samogitia and Gotland (the latter sold to Denmark in exchange for peace in 1409), it wasn't the crushing victory supporters promised and nobles, eager for more land and glory, grumbled about their lords' lack of resolve. Most importantly, it didn't give Poland the outlet to the sea they so badly craved to establish their place as a world power.
To the Teuton mind any surrender, any loss or compromise in their crusade was an insult to God. As the snows melted in the Spring of 1411 several notable men, including Komtur Michael von Sternberg, argued that if von Plauen had simply refused to negotiate more mercenaries and knights would come from Western Europe to reverse this disaster. The growing middle class out of Danzig hated the ruinous taxes they had to pay to fund several thousand ransoms.
Teutonic Order, 1411 (Neumark not shown)
In the end the Peace of Thorn only guaranteed there would be another round. The Baltic Crusade didn't end with the Christianization of Lithuania. Not by a long shot.