On June 24, 1241 .Tsar Ivan Asen II dies. According to the sources, the Bulgarian ruler died around the feast of St. John (June 24). This happened on the eve of the great Ottoman invasion of the Balkans. Under Tsar Ivan Asen II, Bulgaria again, but briefly, extended to the Black Sea, the Aegean Sea and the Adriatic Sea. The reason is that Tsar Ivan Asen II does not build a battle fleet, but prefers to give letters to Dobrovnik to trade, but also to guard the trade routes.
After the death of the monarch, the kingdom is divided between his sons
Tsar Ivan Asen II (1218 - 1241) was a great diplomat and politician, the son of Tsar Asen I. Due to the persecutions of the supporters of Asenevtsi, undertaken by Tsar Boril after the usurpation of the Bulgarian throne (1207), Ivan Asen II was forced to seek salvation together with his younger brother Alexander outside the borders of Bulgaria. He first settled with the Cumans, and from there he moved to the Principality of Galicia-Volhynia, recalls "Wikipedia".
Taking advantage of the acute dissatisfaction with Boril's rule, in 1218 he invaded Bulgaria and with the help of Russian troops took the throne. As a ruler he showed exceptional qualities.
Established a strong central authority and ended internal strife. He strove to maintain peaceful relations with neighboring countries. He established friendly relations with the Magyars by marrying the daughter of the Hungarian king Andrew II - Anna, and in return received the Belgrade and Braničevo regions, which were separated from the Bulgarian state during the reign of Boril.
Tsar Ivan Assen II concluded a treaty with the Epirus despot Theodore Comnenus, who, in his quest to expel the Latins from Constantinople, also needed peace with the Bulgarians.
Established peaceful relations with the Latins and with the Serbs.
Tsar Ivan Asen II also showed himself as an experienced general.
Challenged by Theodore Comnenus, who in 1224 proclaimed himself emperor and in 1230 broke the treaty with the Bulgarian ruler and entered the south-eastern borders of Bulgaria, the Bulgarian ruler completely defeated him in the Battle of Klokotnis in 1230.
Theodore Comnenus himself was captured and taken to Tarnovo. As a result of this victory, he annexed part of the lands of the Epirus state to Bulgaria, and it reached its greatest expansion. Its borders reached the Black, Aegean and Adriatic seas. It became the largest and strongest country on the Balkan Peninsula. The territorial expansion of the Bulgarian state caused serious concerns among the Latins. In order to prevent the danger of a possible invasion by them, Tsar Ivan Assen II started negotiations with the Nicaeans.
In 1232, under the influence of the Pope, the Magyars embarked on a campaign to the east, but were repulsed by the Bulgarian troops.
In 1233, Tsar Ivan Assen II broke the union with the Pope, established in 1204 by Tsar Kaloyan,
since the Roman Curia was the patron of the Latins. After the establishment of a military alliance with the Nicaeans in 1235, he undertook a joint campaign against the Latin Empire, which ended without success. Soon after, fearing an impending crusade, Tsar Ivan Assen II severed his relations with the Nicaeans and changed his hostile stance towards the Latins.
After the campaign of 1239 almost did not affect the borders of the Bulgarian state, Tsar Ivan Asen II tried to improve his relations with the Nicaeans again, but soon died.
Thus, for less than a quarter of a century, without waging many wars, Tsar Ivan Asen II left behind a state huge in its territorial dimensions.
Bulgaria has become the most significant factor on the Balkan Peninsula.
Although during the greater part of his reign, Tsar Ivan Asen II paid more attention to his relations with neighboring countries, he contributed not a little to the development of the internal political life of the country.
During his time there was a real economic and cultural flourishing. Bulgaria's trade relations with the neighboring Balkan countries have grown. Bulgarian merchants also established direct contact with the Adriatic republic of Ragusa (Dubrovnik).
The revival in economic life caused a great need for money. This led to the minting of Bulgarian coins - copper, silver and gold, which was done for the first time in the history of the Bulgarian state. After breaking the union with the Pope, Tsar Ivan Asen II re-established the Bulgarian Patriarchate (1235). With a number of certificates, he provided generous donations to a large number of Bulgarian churches and monasteries.
During his stay in the Principality of Galicia-Volhynia
Ivan - Asen marries Anna,
from the marriage with whom he has two daughters (the name of only one of them is known – Maria). From his marriage to the Hungarian princess Anna - Maria (concluded 1221), he had four children: Elena, Tamara, Kaliman and a child whose gender and name are unknown. More recent studies state that Theodore Comnenus proclaimed himself emperor in 1228 (or 1227), placing the union between the State of Epirus and Bulgaria in the post-coronation period.
The union was sealed by a dynastic marriage between the daughter of the Bulgarian king Maria and the despot Manuel, brother of the Thessaloniki emperor. In 1228, the Latin emperor Robert de Courtenay died and his younger brother Baudouin II was proclaimed emperor. In science, there is the thesis that the Latin barons offered the Bulgarian king a dynastic marriage between the minor Baudouin and a daughter of Ivan Asen II. It is in the context of these Bulgarian-Latin negotiations that the reason for the sudden march of Theodore Comnenus against Bulgaria, which ended with his defeat at Klokotnitsa (March 9, 1230), must be sought.
There are also opinions categorically rejecting the thesis of a Bulgarian-Latin union, but accepting that in reality in 1228 the Latin barons undertook a diplomatic move with the aim of neutralizing the Bulgarian-Epirian union.
Tsar Ivan Assen II annexed a large part of Thrace, Macedonia, Great Wallachia and Albania to the Bulgarian territories. In 1231, Jean de Brienne was proclaimed Latin Emperor, and Tsar Ivan Assen II sought rapprochement with the Nicaean Empire. In more recent studies, the thesis is expressed that Tsar Ivan Assen broke the union with Rome as early as 1231 and the invasions of the Hungarians in the area of Belgrade and Branicevo (1232) were inspired by Pope Gregory IX. The collapse of Theodore Comnenus at Klokotnica also led to the dethronement by the Serbian authorities of his son-in-law, the Serbian king Radoslav (1227 - 1233) and the enthronement of his brother Stefan Vladislav (1233 - 1243), who was married to the daughter of the Bulgarian king.
In 1235, the Bulgarian-Nicene union was sealed with a dynastic marriage
between the eight-year-old Elena and the eleven-year-old son of Ioan Vatazzi - Theodore Laskaris. According to the clauses of the treaty, the Nicaean emperor must assist in the restoration of the Bulgarian patriarchate. In 1235, at the council in Lampsak, Archbishop Joakim was ordained as the Bulgarian patriarch under the name Joakim I.
In the summer of 1235, Bulgarians and Nicaeans launched an unsuccessful siege of Constantinople. The death of Jean de Brienne in 1237 led to the conclusion of an anti-Nicene Bulgarian-Latin alliance, the manifestation of which was the siege of the Tsurulum (Chorlu) fortress. The plague epidemic in Tarnovo, as well as the death of the Bulgarian queen and one of Ivan Asen II's children, led to the renewal of alliance relations with the Nicene Empire.
According to the sources, Ivan Asen II died around the feast of St. John (June 24) 1241. In 1230, Ivan Asen visited Sveta Gora and issued a chrysovule for the Vatoped Monastery of Sveta Gora. The Zograf Monastery was also richly endowed. In the same year, the Bulgarian tsar issued a charter (Dubrovniska charter), with which Dubrovnik merchants were granted the right to free trade in Bulgarian lands.