Editing Constantine XI Palaiologos (section)

=== Initial concerns ===
[[File:One eighth stavraton, 1448-1453, Constantinople.jpg|thumb|1/8 ''[[stavraton]]'', minted 1448–1453. One of the last coins minted by the [[Byzantine Empire]], the coin features a bust of Constantine XI (left) and [[Christ Pantocrator]] (right).]]
One of Constantine's most pressing concerns was the Ottomans. One of his first acts as emperor, just two weeks after arriving in the capital, was to attempt to secure the empire by arranging a truce with Murad II. He sent an ambassador, [[Andronikos Iagaris]], to the sultan. Iagaris was successful, and the agreed-upon truce also included Constantine's brothers in the Morea to secure the province from further Ottoman attacks.{{Sfn|Nicol|1992|p=|pp=40–41}} In order to remove his rebellious brother Demetrios from the capital and its vicinity, Constantine had made Demetrios his replacement as Despot of the Morea to rule the despotate alongside Thomas. Demetrios was granted Constantine's former capital, Mystras, and given authority over the southern and eastern parts of the despotate, while Thomas ruled the northwest and [[Corinthia]] alternating between [[Patras]] and [[Leontari, Arcadia|Leontari]] as his place of residence.{{Sfn|Gilliland Wright|2013|p=63}}
[[File:Σφραγίς Κωνσταντίνου Παλαιολόγου.png|thumb|Constantine XI's seal as emperor]]
Constantine tried to hold numerous discussions with the anti-unionists in the capital, who had organized themselves as a ''[[synaxis]]'' to oppose Patriarch Gregory III's authority, on account of him being a unionist. Constantine was not a fanatical unionist and merely viewed the Union of the Churches as necessary for the empire's survival. The unionists found this argument to be baseless and materialistic, believing that help would be more likely to come through trust in God than a western crusading campaign.{{Sfn|Nicol|1992|p=41}}

Another pressing concern was the continuation of the imperial family as neither Constantine nor his brothers had male children at the time. In February 1449, Constantine had sent [[Manuel Dishypatos]] as an envoy to Italy to speak with [[Alfonso V of Aragon]] and Naples in order to secure military aid against the Ottomans and forge a marriage alliance. The intended match was the daughter of [[Peter, Duke of Coimbra|Alfonso's nephew]], [[Beatrice of Coimbra]], but the alliance failed. In October 1449, Constantine sent Sphrantzes to the east to visit the [[Empire of Trebizond]] and the [[Kingdom of Georgia]] and see if there were any suitable brides there. Sphrantzes, accompanied by a large retinue of priests, nobles, musicians and soldiers, left the capital for nearly two years.{{Sfn|Nicol|1992|p=|pp=42–43}}

While at the court of Emperor [[John IV of Trebizond|John IV Megas Komnenos]] in Trebizond, Sphrantzes was made aware that Murad II had died. Though John IV saw this as positive news, Sphrantzes was more anxious: the old sultan had grown tired and had given up all hope of conquering Constantinople. His young son and successor, [[Mehmed the Conqueror|Mehmed II]], was ambitious, young and energetic. Sphrantzes had the idea that the sultan could be dissuaded from invading Constantinople if Constantine married Murad II's widow, [[Mara Branković]]. Constantine supported the idea when he received Sphrantzes' report in May 1451 and sent envoys to Serbia, where Mara had returned to after Murad II's death.{{Sfn|Nicol|1992|p=|pp=44–46}} Many of Constantine's courtiers opposed the idea due to a distrust of the Serbians, causing Constantine to question the viability of the match.{{Sfn|Hellebuyck|2006|p=36}}{{better source needed|date=March 2023}} Ultimately, the opposition of the courtiers to the marriage proved pointless: Mara had no wish to remarry, as she vowed to live a life of celibacy and chastity for the rest of her life once released from the Ottomans. Sphrantzes then decided that a Georgian bride would suit the emperor best and returned to Constantinople in September 1451, bringing a Georgian ambassador with him. Constantine thanked Sphrantzes for his efforts and they agreed that Sphrantzes was to return to Georgia in the spring of 1452 and forge a marriage alliance. Due to mounting tensions with the Ottomans, Sphrantzes ultimately did not return to Georgia.{{Sfn|Nicol|1992|p=|pp=44–46}}

On 23 March 1450, Helena Dragaš died. She was highly respected among the Byzantines and was mourned deeply. Gemistus Pletho, the Moreot philosopher previously at Constantine's court in the Morea, and [[Gennadius Scholarius|Gennadios Scholarios]], future Patriarch of Constantinople, both wrote funeral orations praising her. Pletho praised Helena's fortitude and intellect, and compared her to legendary Greek heroine [[Penelope]] on account of her prudence. Constantine's other advisors were often at odds with the emperor and each other.{{Sfn|Nicol|1992|p=|pp=46–47}} Her death left Constantine unsure of which advisor to rely on the most.{{Sfn|Hellebuyck|2006|p=34}}{{better source needed|date=March 2023}} [[Andronikos Palaiologos Kantakouzenos]], the ''[[megas domestikos]]'' (or commander-in-chief), disagreed with the emperor on a number of matters, including the decision to marry a Georgian princess instead of an imperial princess from Trebizond. The most powerful figure at the court was Loukas Notaras, an experienced statesman and ''[[megas doux]]'' (commander-in-chief of the navy). Although Sphrantzes disliked Notaras,{{Sfn|Nicol|1992|p=|pp=46–47}} he was a close friend of Constantine. As the Byzantine Empire no longer had a navy, Notaras' position was more of an informal prime minister-type role than a position of military command. Notaras believed that Constantinople's massive defenses would stall any attack on the city and allow western Christians to aid them in time. Due to his influence and friendship with the emperor, Constantine was likely influenced by his hopes and ideas.{{Sfn|Hellebuyck|2006|p=|pp=29–30}}{{better source needed|date=March 2023}} Sphrantzes was promoted to "First Lord of the Imperial Wardrobe": his office gave him near unhindered access to the imperial residence and a position to influence the emperor. Sphrantzes was even more cautious towards the Ottomans than Notaras, and believed the ''megas doux'' risked antagonizing the new sultan. Although Sphrantzes also approved of appealing to the west for aid, he believed that any appeals had to be highly discreet in order to avoid Ottoman attention.{{Sfn|Hellebuyck|2006|p=|pp=30–31}}{{better source needed|date=March 2023}}