Poland during the Jagiellon dynasty in the context of Lithuanian people

The history of Lithuania dates back to settlements founded about 10,000 years ago, but the first written record of the name for the country dates back to 1009 AD. Lithuanians, one of the Baltic peoples, later conquered neighboring lands and established the Grand Duchy of Lithuania in the 13th century (and also a short-lived Kingdom of Lithuania). The Grand Duchy was a successful and lasting warrior state. It remained fiercely independent and was one of the last areas of Europe to adopt Christianity (beginning in the 14th century). A formidable power, it became the largest state in Europe in the 15th century spread from the Baltic Sea to the Black Sea, through the conquest of large groups of East Slavs who resided in Ruthenia.

In 1385, the Grand Duchy formed a dynastic union with Poland through the Union of Krewo. Later, the Union of Lublin (1569) created the Polish–Lithuanian Commonwealth. During the Second Northern War, the Grand Duchy sought protection under the Swedish Empire through the Union of Kėdainiai in 1655. However, it soon returned to being a part of the Polish–Lithuanian state, which persisted until 1795 when the last of the Partitions of Poland erased both independent Lithuania and Poland from the political map. After the dissolution, Lithuanians lived under the rule of the Russian Empire until the 20th century, although there were several major rebellions, especially in 1830–1831 and 1863.

The (First) Peace of Thorn was a peace treaty formally ending the Polish–Lithuanian–Teutonic War between allied Kingdom of Poland and Grand Duchy of Lithuania on one side, and the Teutonic Knights on the other. It was signed on 1 February 1411 in Thorn (Toruń), one of the southernmost cities of the Monastic State of the Teutonic Knights. In historiography, the treaty is often portrayed as a diplomatic failure of Poland–Lithuania as they failed to capitalize on the decisive defeat of the Knights in the Battle of Grunwald in June 1410. The Knights returned Dobrzyń Land which they captured from Poland during the war and made only temporary territorial concessions in Samogitia, which returned to Lithuania only for the lifetimes of Polish King Władysław Jagiełło and Lithuanian Grand Duke Vytautas. The Peace of Thorn was not stable. It took two other brief wars, the Hunger War in 1414 and Gollub War in 1422, to sign the Treaty of Melno that solved the territorial disputes. However, large war reparations were a significant financial burden on the Knights, causing internal unrest and economic decline. The Teutonic Knights never recovered their former might.