Editing Manuel II Palaiologos (section)

===Renewed Ottoman sieges===
The Ottomans under [[Bayezid I]] were themselves crushingly defeated by [[Timur]] at the [[Battle of Ankara]] in 1402. As the sons of Bayezid I struggled with each other over the succession in the [[Ottoman Interregnum]], John VII was able to secure the return of the European coast of the [[Sea of Marmara]] and of Thessalonica to the Byzantine Empire in the [[Treaty of Gallipoli]]. When Manuel II returned home in 1403, his nephew duly surrendered control of Constantinople and received as a reward the governorship of newly recovered Thessalonica. The treaty also regained from the Ottomans Mesembria (1403–1453), [[Varna, Bulgaria|Varna]] (1403–1415), and the Marmara coast from [[Üsküdar|Scutari]] to [[İzmit|Nicomedia]] (between 1403–1421).

[[File:Map of the southern Balkans, 1410.svg|thumb|right|Map of the southern Balkans and western Anatolia in 1410, following the Treaty of Gallipoli]]
[[File:Manuel II - half stavraton - sb2551.jpg|thumb|Half ''[[stavraton]]'' coin by Manuel. On the reverse, Manuel's bust.]]

However, Manuel II kept contact with Venice, Genoa, Paris and Aragon, by sending envoy Manuel Chrysoloras in 1407–8, pursuing to form a coalition against the Ottomans.{{sfn|Çelik|2021|p=260}}

On 25 July 1414, with a fleet consisting of four galleys and two other vessels carrying contingents of infantry and cavalry, departed Constantinople for Thessalonica. The purpose of this force soon became clear when he made an unannounced stop at [[Thasos]], a normally unimportant island which was then under threat from a son of the lord of Lesbos, Francesco Gattilusio. It took Manuel three months to reassert imperial authority on the island. Only then did he continue on to Thessalonica, where he was warmly met by his son [[Andronikos Palaiologos (son of Manuel II)|Andronicus]], who then governed the city.

In the spring of 1415, he and his soldiers left for the Peloponnese, arriving at the little port of Kenchreai on Good Friday, 29 March. Manuel II Palaiologos used his time there to bolster the defences of the [[Despotate of Morea]], where the Byzantine Empire was actually expanding at the expense of the remnants of the [[Latin Empire]]. Here Manuel supervised the building of the ''[[Hexamilion]]'' (six-mile wall) across the [[Isthmus of Corinth]], intended to defend the [[Peloponnese]] from the Ottomans.

Manuel II stood on friendly terms with the victor in the Ottoman civil war, [[Mehmed I]] (1402–1421), but his attempts to meddle in the next contested succession led to a new [[Siege of Constantinople (1422)|assault on Constantinople]] by [[Murad II]] (1421–1451) in 1422. During the last years of his life, Manuel II relinquished most official duties to his son and heir [[John VIII Palaiologos]], and went back to the West searching for assistance against the Ottomans, this time to the King Sigismund of Hungary, staying for two months in his court of [[Buda]]. Sigismund (after suffering a defeat against the Turks in the Battle of Nicopolis in 1396) never rejected the possibility of fighting against the Ottoman Empire. However, with the [[Hussite wars]] in Bohemia, it was impossible to count on the Czech or German armies, and the Hungarian ones were needed to protect the Kingdom and control the religious conflicts.<ref>Szalay, J. y Baróti, L. (1896). A Magyar Nemzet Története. Budapest, Hungría: Udvari Könyvkereskedés Kiadó.</ref> Unhappily Manuel returned home with empty hands from the Hungarian Kingdom, and in 1424 he and his son were forced to sign an unfavourable peace treaty with the Ottoman Turks, whereby the Byzantine Empire had to pay tribute to the sultan.