Anna (Anisia)
Anna, subsequently known under the religious name Anisia( Анисия), was the first wife of Tsar Ivan Asen II of Bulgaria( r. 1218 – 1241) and empress consort of the Second Bulgarian Empire from 1218 to 1221.
She was exiled to a monastery in the beginning of Ivan Asen's reign, after he arranged his marriage to Anna Maria of Hungary.
From his marriage to Anna, Ivan Asen had two children.
Peter (sevastokrator)
Peter was a Bulgarian nobleman who held the high title of" sevastokrator" around 1253.
He married a daughter of Ivan Asen II of Bulgaria.
He ruled significant territories in Bulgaria during the reign of his brother- in- law, Michael II Asen.
Irene Komnene Doukaina
Irene Komnene Doukaina or Eirene Komnene Doukaina was an Empress of Bulgaria during the Second Bulgarian Empire and Byzantine princess.
She was the third wife of tsar Ivan Asen II of Bulgaria.
She was the mother of tsar Michael Asen I of Bulgaria.
Elena-Evgenia, wife of Ivan Asen I
Elena was the second wife of tsar Ivan Asen I of Bulgaria.
She was the mother of tsar Ivan Asen II of Bulgaria.
Irene Palaiologina, Empress of Bulgaria
Irene Palaiologina was the eldest daughter of Byzantine emperor Michael VIII Palaiologos and empress Theodora Palaiologina, and empress consort of Ivan Asen III of Bulgaria.
Ivan Asen IV of Bulgaria
Ivan Asen , also known as Ivan Asen IV was a Bulgarian Prince, third son of Emperor Ivan Alexander from his first wife Theodora of Wallachia.
He was born c. 1326.
Little is known about him.
In the eighteenth year of the reign of Ivan Alexander - i. e. 1349 - he and his troops faced a 20,000-strong Ottoman army under the command of Murad
I's elder brother Syuleiman.
The fierce battle between Bulgarians and Turks took place in the area around Sofia.
According to the Anonymous Bulgarian chronicle, "the Turks killed Asen and a great number of Bulgarians"; according to Ottoman chronicles "many jannisaries perished" in the battle.
That shows that the battle claims many casualties from both sides and Ivan Asen perished fighting bravely for his country.
It seems that despite the great losses the Bulgarians had repulsed the enemy as the next recorded Ottoman invasion occurred 6 years later, in 1355, when in the battle of Ihtiman
the Ottoman Turks killed Asen's eldest brother, Michael Asen.
Ivan Asen IV married a Wallachian Princess and had two daughters.
Ivan Asen II of Bulgaria
Ivan Asen II, also known as John Asen II or John Asan II( 1190s – May/ June 1241), was emperor( or tsar) of Bulgaria from 1218 to 1241.
He was still a child when his father Ivan Asen Ione of the founders of the Second Bulgarian Empirewas killed in 1196.
His supporters tried to secure the throne for him after his uncle, Kaloyan, was murdered in 1207, but Kaloyan's other nephew, Boril, overcame them.
Ivan Asen fled from Bulgaria and settled in the Rus' principalities.
Boril could never strengthen his rule which enabled Ivan Asen to muster an army and return to Bulgaria.
He captured Tarnovo and blinded Boril in 1218.
Initially, he supported the full communion of the Bulgarian Church with the Papacy and concluded alliances with the neighboring Catholic powers, Hungary and the Latin Empire of Constantinople.
He tried to achieve the regency for the 11- year- old Latin Emperor, Baldwin II, after 1228, but the Latin aristocrats did not support Ivan Asen.
He inflicted a crushing defeat on the Empire of Thessalonica, Theodore Komnenos Doukas, in the Battle of Klokotnitsa in 1230.
Theodore's empire soon collapsed and Ivan Asen conquered large territories in Macedonia, Thessaly and Thrace.
The control of the trade on the Via Egnatia enabled Ivan Asen to implement an ambitious building program in Tarnovo and struck gold coins in his new mint in Ohrid.
He started negotiations about the return of the Bulgarian Church to Orthodoxy after he learnt that the barons of the Latin Empire had elected John of Brienne regent for Baldwin II in 1229.
Ivan Asen and the Emperor of Nicaea, John III Vatatzes, concluded an alliance against the Latin Empire at their meeting in 1235.
During the same conference, the rank of patriarch was granted to the head of the Bulgarian Church in token of its autocephaly( or independence).
Ivan Asen and Vatatzes joined their forces in attacking Constantinople, but Ivan Asen realized that Vatatzes could primarily take advantage of the fall of the Latin Empire and broke off his alliance with Nicaea in 1237.
After the Mongols invaded the Pontic steppes, several Cuman groups fled to Bulgaria, causing much destruction in the country during the last years of Ivan Asen's rule.
Maria Asenina of Bulgaria
Maria Asenina of Bulgaria was a Bulgarian princess and empress consort.
She was the consort of Emperor Mitso Asen of Bulgaria( reigned 1256 – 1257).
She was the daughter of Emperor Ivan Asen II of Bulgaria and Empress Irene Komnene of Epirus.
Through her mother, she was a granddaughter of Theodore of Epirus.
She is mother of Bulgarian Emperor Ivan Asen III( r. 1279 – 1280) and of Bulgarian Empress Kira Maria, who married Emperor George I of Bulgaria.
Ivan Asen III of Bulgaria
Ivan Asen III( also Йоан Асен III," Ioan Asen III", and in English" John Asen III"), ruled as tsar of Bulgaria 1279 – 1280.
Ivan Asen III was the son of Mitso Asen of Bulgaria and Maria of Bulgaria, a daughter of Ivan Asen II of Bulgaria and Irene of Thessalonica.
He was probably born in about 1259/ 60, and died in exile in 1303.
Fearing the rapid success of Ivaylo of Bulgaria, the Byzantine Emperor Michael VIII Palaiologos summoned Ivan Asen to his court, granted him the title of" despotēs", and married him to his eldest daughter Irene Palaiologina in 1277 or 1278.
Michael VIII then sent several Byzantine armies to attempt to assert Ivan Asen III on the throne of Bulgaria.
Although Ivailo defeated several of these attempts, he was blockaded for three months in Drăstăr( Silistra) by the Mongol allies of Michael VIII.
In the interval a Byzantine force besieged the Bulgarian capital Tărnovo and, hearing a rumor of Ivailo's death in battle, the local nobility surrendered and accepted Ivan Asen III as emperor in 1279.
To strengthen his position in Tarnovo, Ivan Asen III married his sister Maria( Kira Maria) to the Bulgaro- Cuman nobleman George Terter, but failed to assert himself throughout the country.
Ivailo reappeared before the walls of the capital and defeated two Byzantine attempts to relieve Ivan Asen III.
Despairing of success, Ivan Asen III and Irene Palaiologina secretly fled Tarnovo with choice treasures from the palace treasury, including pieces captured from defeated Byzantine Emperors in former victories.
Reaching Mesembria( Nesebăr), the imperial couple sailed for Constantinople, where the enraged Michael VIII refused to receive them for days for their cowardice.
In 1280 or 1281 Ivan Asen III traveled to the Golden Horde, competing with Ivailo in a bid to win support for restoration in Bulgaria.
The Mongol chieftain Nogai Khan eventually had Ivailo murdered, but failed to restore Ivan Asen III in Bulgaria.
The latter returned to his family possessions in the Troad, and died in 1303.
Theodora of Wallachia
Theodora  of Wallachia was the daughter of Basarab I of Wallachia (r. 1310–1352) and Lady Margareta.
She married Ivan Alexander of Bulgaria as his first wife.
This marriage produced four children — Michael Asen, Ivan Sratsimir, Ivan Asen and Vasilisa.
In 1345 Tsar Ivan Alexander divorced Tsaritsa Theodora and sent her into a monastery as a nun under the name Teofana.

Question: Who is the maternal grandfather of Ivan Asen Iv Of Bulgaria?