At its greatest territorial extent during the early 15th century, the State encompassed Chełmno Land, Courland, Gotland, Livonia, Estonia, Neumark, Pomerelia (Gdańsk Pomerania), Prussia and Samogitia.

Throughout its history, the Teutonic state waged numerous wars with Poland[4] and Lithuania, encouraging the two countries to form a close alliance and personal union, which eventually led to the creation of the Polish–Lithuanian Commonwealth in the 16th century.

[1] The monastic state of the Order's main (Prussian) branch was secularized in 1525 during the Protestant Reformation to become the Duchy of Prussia ruled by the House of Hohenzollern, remaining a fiefdom of the Polish Crown and later the Polish–Lithuanian Commonwealth.

Early in 1224, Emperor Frederick II announced at Catania that Livonia, Prussia with Sambia, and a number of neighboring provinces were under imperial immediacy.

At the end of 1224, Pope Honorius III announced to all Christendom his appointment of Bishop William of Modena as the Papal Legate for Livonia, Prussia, and other countries.

Under their governance, woodlands were cleared and marshlands made arable, upon which many cities and villages were founded, including Marienburg (Malbork) and Königsberg (Kaliningrad).

[12] The cities were heavily fortified, accounting for the long lasting conflicts with the resistive native Old Prussians, with armed forces under command of the knights.

The assimilation of the Livonian Brothers of the Sword (established in Livonia in 1202) increased the Teutonic Order's lands with the addition of the territories known today as Latvia and Estonia.

In 1243, the Papal legate William of Modena divided Prussia into four bishoprics: Culm (Chełmno), Pomesania, Ermland (Warmia) and Samland (Sambia).

The Order had been called by King Władysław I of Poland to help repel a Brandenburgian invasion; however, the Teutonic Knights themselves began to occupy the city and the region.

The Teutonic Knights then carried out a massacre of the inhabitants of the city, killing up to 10,000 people according to medieval sources, although the exact number of victims is a subject of disputes.

[12] Thus Prussian merchants, along with those from Ditmarsh, were the only beneficiaries of a quasi membership within the Hansa, although lacking the background of citizenship in a fully autonomous or free city.

[17] The Teutonic Order's annexation and possession of Gdańsk (Danzig) and the surrounding region was consistently disputed by the Polish kings Władysław I and Casimir III the Great – claims that led to the Polish–Teutonic War (1326–1332) and, eventually, lawsuits in the papal court in 1320 and 1333, which ruled in favor of Poland, however, the Teutonic Knights did not comply and continued to occupy the annexed Polish territories.

[19] But when Valdemar IV then captured Prussian merchant ships in the Øresund on their way to England, Grand Master Winrich of Kniprode travelled to Lübeck to propose a war alliance against Denmark, accepted with some reluctance only by the important cities forming the Wendish-Saxon third of the Hanse.

[26] Dissatisfied Richard II's navy suddenly attacked six Prussian ships in May 1385 – and those of more Hanse members – in the Zwin,[28] Grand Master Conrad Zöllner von Rothenstein immediately terminated all trade with England.

[28] When in the same year the Hansa evacuated all their Danish castles in fulfillment of the Treaty of Stralsund, Prussia argued in favour of a renewal of the Cologne Federation for the deeply concerned about the ensuing conflict with England, but could not prevail.

[28] So when in 1388 Richard II finally reconfirmed the Hanseatic trade privileges, Prussia once again permitted merchant adventurers, granting permissions to remain; for this action they were renounced once again by the Grand Master Conrad of Jungingen in 1398.

This officer was in charge of the considerable commerce, import, export, crediting, real estate investment etc., which the Order carried out, using its network of bailiwicks and agencies which spanned much of Central, Western and Southern Europe as well as the Holy Land.

[25] Since the late 1380s grave piracy by privateers, promoted by Albert of Sweden and Mecklenburg actually directed against Margaret I of Denmark, blocked seafaring to the herring supplies at the Scania Market; thus fish prices tripled in Prussia.

Poland and Lithuania triumphed following a victory at the Battle of Grunwald (Tannenberg), which marked the start of the decline of the State of the Teutonic Order, and the rise of the Polish–Lithuanian union as a major power in Central and Eastern Europe.

[37] The Order assigned Heinrich von Plauen to defend Teutonic-held Eastern Pomerania (Pomerelia), who moved rapidly to bolster the defence of Marienburg Castle in Pomesania.

Eventually von Plauen was promoted to Grand Master and, in 1411, concluded the First Treaty of Thorn with King Władysław II Jagiełło of Poland.

[1] In accordance to the peace treaty, from now on, every Grand Master was obliged to swear an oath of allegiance to the reigning Polish king within six months of taking office, and any new territorial acquisitions by the Teutonic Order, also outside Prussia, would also be incorporated into Poland.

[41] While the Knights of the Teutonic Order formed a thin ruling class by themselves, they extensively used mercenaries, mostly German, from the Holy Roman Empire, to whom they granted lands in return.

Due to several factors, among which was the high rate of early death in battle, these lands became concentrated over time in the hands of a relatively small number of noblemen each having a vast estate.

In 1525, during the aftermath of the Polish-Teutonic War (1519–1521), Sigismund I the Old, King of Poland, and his nephew, the last Grand Master of the Teutonic Knights, Albert of Brandenburg-Ansbach, a member of a cadet branch of the House of Hohenzollern, agreed that the latter would resign his position, adopt Lutheran faith and assume the title of Duke of Prussia.

Fortifications of the Teutonic State have been examined through archaeological excavation since the end of World War II, especially those built or expanded during the 14th century.

Fortifications are generally the best preserved material legacy of the Order's presence in the Baltic today, and timber and earth, as well as brick examples, are attested in the archaeological record.

[44] Where they followed the conventional layout, castles included a connected set of communal spaces such as a dormitory, refectory, kitchen, chapter house, a chapel or church, an infirmary, and tower projecting over the moat.

Sinc Mary was the most important patron of the knights and central to the liturgy of the Teutonic Order, it is not surprising to find such striking representations of her at its most prominent castle.