1386

1386 was a year marked by significant political realignments across Europe, including the formation of long-lasting alliances and the consolidation of regional power.

In Central Europe, the Polish–Lithuanian union began to take shape as Jogaila, ruler of Lithuania, agreed to be baptized as a Christian and to marry Jadwiga of Poland. This arrangement created a personal union between Poland and Lithuania and laid the groundwork for a combined Polish-Lithuanian state in the following decades, contributing to the political and religious shaping of the region.

In the Swiss Confederation, the Battle of Sempach on July 9 ended with a decisive Swiss victory over the Habsburgs. The engagement reinforced Swiss hopes for greater autonomy and strengthened the emerging federation, while the death of Leopold III of Austria at the battle underscored the high stakes of the conflict in the region.

Across the western Atlantic archipelago and Iberia, the year also saw the continued growth of transnational alliances. The Treaty of Windsor was concluded between England and Portugal, formalizing a strategic alliance that would endure for centuries and influence military and maritime cooperation in the Iberian and Atlantic theaters.

Notable deaths of the year included Leopold III of Austria, whose death in battle symbolized the ongoing power struggles within the Holy Roman Empire and its borderlands.

1386 thus stands as a year of foundational shifts: the Polish–Lithuanian union began its long trajectory, Swiss independence continued to consolidate after Sempach, and long-standing Anglo–Portuguese ties were reinforced, shaping alliances for the late medieval period.