As early as the autumn of 1389, the army of the Hungarian King Sigismund (1368–1437) crossed the Sava, invaded the Serbian lands and seized the fortresses of Borač and Čestin. In such circumstances, the assembly of the Serbian nobility, headed by the young Stefan and Princess Milica, with the support of Patriarch Spiridon (1380–1389), decided to seek peace with the Ottomans and to recognize their supreme authority. The peace treaty with Sultan Bayezid (c. 1360–1403) was concluded in the first half of 1390. Under the terms set by the Ottomans, Moravian Serbia undertook to pay tribute and, when needed, to send auxiliary troops to the Turkish army. Stefan's sister Olivera was sent to the harem of Sultan Bayezid, while Stefan was obliged to come to the Sultan's court and confirm his loyalty [ŽDS 23]. After the signing of the treaty, Turkish units helped the Serbs to recover the fortresses that the Hungarians had earlier seized.
Stefan ruled independently as a regional lord, that is, as Serbian prince, from 1393. By force of military and political circumstances, a young man inclined toward letters became a warrior of exceptional skill and courage. Being compelled to place himself in the service of the Ottomans, as an Ottoman vassal he led Serbian auxiliary troops in the wars waged by the conquerors from the East, including taking part on the side of the Turks in various engagements, among others in the battles of Rovine in 1395 [ŽDS 33], Nicopolis in 1396 [ŽDS 36], and finally Ankara (Angora) in 1402.
After the Battle of Ankara, in which Despot Stefan Lazarević displayed exceptional courage and military skill, thereby arousing the admiration even of his adversary, the victor in that battle -
the Tatar emir Tamerlane (1336–1405), the situation in the Serbian lands and in the Balkans changed, and Stefan's position was considerably strengthened. During the battle, Prince Stefan was wounded, while his nephew Grgur Vuković Branković (†1408), the son of Vuk Branković and Mara Lazarević, an important representative of the Serbian nobility, was taken captive, but was later ransomed. During the battle itself or immediately after it, Stefan's sister Olivera was also captured. She, however, was likewise soon freed, as the result of an agreement that Stefan's envoy concluded with Tamerlane [ŽDS 40]. Soon after the battle, the Byzantine Emperor John VII Palaiologos (1370–1408) conferred upon Stefan in Constantinople the title of despot [ŽDS 41–42], which was one of the highest ruling titles in the hierarchy of the Eastern Roman Empire of that time. Later, Stefan's sovereign dignity as despot was also confirmed by the Eastern Roman Emperor Manuel II Palaiologos (1350–1425), who conferred the rank of despot upon him a second time [ŽDS 60].
Stefan consolidated his political position by concluding an alliance with the Hungarian King Sigismund. In confirmation of this alliance, Sigismund ceded to Stefan the territories of Mačva and Belgrade, as well as important fortresses, such as those of Belgrade and Golubac on the Danube, later also Srebrenica - a rich mine in eastern Bosnia - and certain other towns. The period after the Battle of Ankara, however, was marked by great tensions and unrest. The Ottoman defeat at Ankara led to civil war in the Ottoman Empire, but it also inflamed internal conflicts in the Serbian lands. The main sources of these conflicts were the tensions between two powerful Serbian families - the Lazarevićes and the Brankovićes - as well as among the members of the Lazarević family themselves. Internal friction in the Serbian lands led even to military campaigns: in Kosovo in 1402 the Lazarevićes faced an attack by Đurađ Branković and Turkish forces. Stefan won a victory in this battle as well [ŽDS 45–46]. The Despot, however, did not strive to destroy his opponents; rather, by his wise and statesmanlike conduct he healed the wounds of discord [ŽDS 47–48]. The conflicts among the Serbian leading men nevertheless lasted for a whole decade more.
The Serbian Despotate at the Time of the Founding of Manasija
The period of Despot Stefan's reign was marked by complex social and historical circumstances. Dynastic conflicts, betrayals, incessant wars and relentless Ottoman expansion brought Serbian society into a state of great uncertainty and fear. That epoch represented one of the most difficult periods in Serbian history, a deep abyss in comparison with the golden age of the Nemanjićes, which had been a symbol of stability, prosperity and spiritual ascent.
The society of that time was permeated by an apocalyptic sense of dread before impending ruin, aware that it stood on the brink of the last times. Yet despite these challenges, the Serbian people did not lose their sense of responsibility and their faith in a better future. Despot Stefan, as ruler, recognized his task: in those hard circumstances, with the help of faith and knowledge, to serve his people in the best possible way. He was aware that, even at the end of the historical course of the Serbian state, it was his duty to preserve and advance what remained of Serbian culture, spirituality and political life.
The troubled times in which Despot Stefan lived and ruled are not only a testimony to tragic circumstances, but also an example of how, in the most difficult periods, one can serve one's people responsibly and with dignity, while preserving their faith, culture and statehood. The success with which Despot Stefan answered this challenge became a symbol of perseverance and an inspiration for future generations.
Around 1405, the Serbian Despot Stefan married Jelena, the daughter of the archon Francesco II Gattilusio, lord of the island of Lesbos - according to Constantine's Life,