Niketas Choniates names "Isaacius et Alexius" as sons of "Andronicus Angelus".
As leader of the aristocrats against whom Emperor Andronikos I had struggled, he succeeded in 1185 on the latter's downfall as Emperor ISAAKIOS II. He immediately attacked the Normans, his general Alexios Branas defeating them at Mosynopolis and Dimitritsa 7 Nov 1185, which resulted in their expulsion from Thessaloniki, Durazzo and Corfu. Isaakios also made peace with Béla III King of Hungary, sealed by the emperor's second marriage with the king's daughter. In 1186, he was faced with the rebellion of Alexios Branas, who had been sent to quell the Bulgarian rebellion of the brothers Ivan Asen and Teodor but, having penetrated rebel territory, used the army for his own interests and led it to Adrianople where he was proclaimed emperor. Branas marched on Constantinople, but was put to flight and killed by loyal forces. Emperor Isaakios led his army personally against Bulgarian rebels, successfully driving them across the Danube. This was followed by further campaigns in Sep 1187 and 1188, but the emperor was forced to recognise Bulgarian independence under a peace treaty signed in 1188. Tensions developed with Emperor Friedrich I "Barbarossa", leader of the Third Crusade, who had received a warm welcome in Serbia and had crossed into Byzantine territory at Branicevo. Anxious to protect his interests, Isaakios signed a treaty of alliance with Saladin, which worsened the situation. After taking Philippopolis [Plovdiv] and Adrianople, as well as threatening Constantinople, Emperor Friedrich forced Emperor Isaakios to give him provisions and ships to cross into Asia Minor. In Sep 1190, Byzantine troops defeated the Serbs at the Morava River, but although the Byzantines regained Niš, Beograd and northern Macedonia including Skopje, under the ensuing peace treaty, they were obliged to recognise Serb independence and Nemanja's right to rule Zeta, southern Dalmatia, Trebinje and Hum. In retaliation for Bulgarian raids on Philippopolis, Sardika [Sofija] and Adrianople, Emperor Isaakios attacked Bulgaria but was heavily defeated in  near Arcadiopolis. The reign of Emperor Isaakios saw a major weakening of Byzantium and was marked by a rapid revival of corruption and administrative abuses, especially increased taxes to establish his luxurious court.
He was deposed 8 Apr 1195 by his older brother Alexios while preparing a further campaign against Bulgaria, and blinded. He was restored as emperor 17 Jul 1203 when the crusading army captured Constantinople and his brother Alexios III had fled, his son being named as co-emperor. Isaakios was deposed end-Jan 1204 in an anti-Latin revolt which broke out in Constantinople, and imprisoned once more.
The necrology of Speyer cathedral records the death "VI Kal Sep" of "Maria regina Philippi regis contectalis, nata de Grecia" and the donations which she made to found the anniversaries "in octava Martini [18 Nov]…patris eius et matris eius…Ysaac et matre Herina" and "fratris…eius et sororis eius tercia die post festum Michahelis [1 Oct]…Manuel fratre, Effrosina sorore". 1