[2] From the marriage with a Polish woman, Sophie Dorothea Jerzębska,[3] was born the future Patriarch's great-grandfather, Yegor (Georgi) von Rüdiger (1811–1848).

[4] After the October Revolution of 1917, Alexey Ridiger's father Mikhail became a refugee and the family settled in Estonia, first in Haapsalu where a shelter was provided by priest Ralph von zur Mühlen.

[7] From his early childhood Alexey Ridiger served in the Orthodox Church under the guidance of his spiritual father, Archpriest Ioann Bogoyavlensky.

On 14 August 1961, he was chosen to be the Orthodox Church Bishop of Tallinn and Estonia, succeeding his father-in-law, John (Alekseev), who was promoted to Archbishop of Gorky and Arzamas.

[12] In 1986 he was released from the post of the Chancellor, which he had held since 1961 and which allowed him to be based in the Moscow Patriarchy's headquarters, and transferred to Leningrad; the decision was effectively made by the Council for Religious Affairs and was later presented by Alexy as punishment for his letter in December 1985 to Mikhail Gorbachev with proposals of reforms to church-state relations.

Shortly after Alexy's death, the then Chairman of the Council Kharchev strongly denied that and said the decision was aimed at "defusing the tense emotional atmosphere within Patriarch Pimen's inner circle".

These reports originate with Gleb Yakunin, a member of the committee created for the investigation of the Soviet coup attempt of 1991 and chaired by Lev Ponomaryov, who thereby gained the access to secret KGB archives.

He published code names of several KGB agents who held high-rank positions in the Russian Orthodox Church including Patriarch Alexius II.

The report detailing his recruitment makes clear that the KGB contacted Alexy, then still a simple priest, because they expected him to succeed John (Alekseev) as Bishop of the Russian Orthodox diocese of Tallinn and Estonia (and he was in fact appointed to this post less than three years later).

[32] Similarly, the official spokesman for the Moscow Patriarchy, Father Vsevolod Chaplin, in 2000 claimed that reports of Patriarch Alexy II being an "associate of the special services" are "absolutely unsubstantiated".

According to Davis (1995), "If the bishops wished to defend their people and survive in office, they had to collaborate to some degree with the KGB, with the commissioners of the Council for Religious Affairs, and with other party and governmental authorities.

"[35] Official records do show that during Patriarch Alexy's tenure as bishop, the Tallinn diocese had a lower number of forced Church closings than was typical in the rest of the USSR.

[36] In the judgement of Ware (1997), "Opinions differ over the past collaboration or otherwise between the Communist authorities, but on the whole he is thought to have shown firmness and independence in his dealings as a diocesan bishop with the Soviet State.

[41] He issued a second appeal against violence and fratricide, which was amplified over loudspeakers to the troops outside the Russian "White House" half an hour before they attacked.

[42] During Alexy II's first official visit to Germany in 1995, the Patriarch publicly apologized for the "Communist tyranny that had been imposed upon the German nation by the USSR".

He had a dispute with Rome over the property rights of the Byzantine Rite Eastern Catholic Churches in Ukraine, which had emerged from Soviet control after the Gorbachev's liberalisation of Russia.

[48] He nevertheless had good relations with Latin Catholics in France and was friends with Cardinal Roger Etchegaray, who invited him to the country shortly before his death.

The Church, according to the Patriarch, "has invariably supported the institution of the family and condemns untraditional relations, seeing them as a vicious deviation from God-given human nature".

[12] In February 2007 a controversy erupted when Diomid, Bishop of Chukotka, condemned the ROC's hierarchy and personally Patriarch Alexy II for ecumenism, supporting democracy and misguided loyalty to the Russian secular authorities.

Shortly before the signing of the Act of Canonical Communion, there were some reports in Russian media claiming that Patriarch Alexy II was in critical condition or even dead.

[60][62] The Patriarch's private residence was located in the village of Lukino (near Peredelkino), now a western suburb of Moscow; it includes a 17th-century church, a museum, and a spacious three-storey house built in the late 1990s.

[64] The formal residence (infrequently used for some official functions) is located in the Moscow Danilov Monastery – a two-storey Soviet building erected in the 1980s.

[68] During the service in the Christ the Saviour Cathedral, which was broadcast live by Russia's state TV channels, after Kathisma XVII had been chanted and Metropolitan Kirill set about doing the incensing round the coffin, he appeared to teeter and, being propped up by two bishops,[69] was ushered into the sanctuary and was absent for about an hour.

"[70][71] The ROC official spokesman Vsevolod Chaplin lashed out at the news media that had reported the incident "incorrectly" insisting that Kirill had not fainted, but merely had "felt unwell".

[72] The following is a selection of quotes from notable obituaries: Patriarch Alexy II was an honorary member of the Theological Academies in St. Petersburg, Moscow and Crete, Greece.