Pact of Vilnius and Radom

The Union of Vilnius and Radom comprised a series of agreements between Lithuania and Poland, which were closed in 1401 in Vilna and confirmed by the Privy Council in Radom in the same year. They supplemented the agreement of Krewo and gave the Grand Duchy of Lithuania substantial internal autonomy.

The agreement strengthened the Polish- Lithuanian Commonwealth and improved especially the legal position of the Lithuanian Duke Vytautas, who was appointed Grand Duke of Lithuania. They determined that in the event of the death of Vytautas Lithuania would fall to his cousin, the Prince Jogaila. If Jogaila died first, Vytautas would have to be consulted in the election of a Polish king. Both - Vytautas as Jogaila - to beget sons hoped that would both inherit the Kingdom of Poland and the Grand Duchy of Lithuania. It should finally be Jogaila, who had herein success.

The Lithuanian boyars confirmed the agreement first in Vilnius, the Polish nobles then in Radom.

Through the agreement, it was Vytautas possible to start a campaign against his former allies, the Teutonic Order. This conflict with the Order subsequently led to the Battle of Tannenberg (1410 ) and the decisive defeat of the Order against the united Polish-Lithuanian army. In 1411 the Order had to cede the 1411 provincial Žemaitėjė back to the Grand Duchy of Lithuania in the first Peace of Thorn.

After the victorious campaign of the Polish -Lithuanian Union against the Teutonic Order in 1410, the Union of Horodło was closed in 1413, the even more connected the two parts of the country together.