Relations between Anglicans and German-speaking Old Catholics began around the year 1870 as the Old Catholic movement was developing in reaction to the papal dogmas of the First Vatican Council. 
The Anglican Churches of England and North America were very interested in the discussions about the First Vatican Council taking place in Europe at the time. The evangelical wing of the English Church saw common cause with the Old Catholics primarily in their opposition to Rome; the anglo-catholic wing on the other hand assumed rightly a commonality with Old Catholics in their keeping the tradition of the “old,” undivided church of the first millennium.
The Old Catholics were also interested in contacts with Anglicans. High-ranking Anglican guests were present at the first gatherings of Old Catholics (which were initially held yearly starting in 1871). A Union Commission was formed at the second gathering in Cologne (1872), which initiated the ecumenical work. The Union Commission, in the presence of Anglican and Orthodox guests of the gathering, formulated several principles which were to be the basis of reunification discussions: the faith of the early church, the acceptance of holy scripture as highest authority, the recognition of the divinity of Christ and of his establishment of the church. All of these principles were to be employed with the historical-critical methods of biblical and dogmatic studies. At the third gathering in Constance in 1873 a Sub-Commission for conversations with Anglicans was established (along with a Sub-Commission for conversations with the Orthodox). Chairman of the former was Ignaz von Döllinger. In 1874 and 1875 he organized the “Bonn Union Conferences,” which were “the most significant ecumenical conversations in the 19th century.” 
The first Bonn Union Conference (1874) accepted fourteen theses, formulated primarily by Döllinger.  The question of the validity of Anglican Orders remained an open one at the Conference. Joseph Hubert Reinkens, elected and consecrated (1873) first Bishop for Old Catholics in the German Reich, as well as Döllinger saw no difficulties in the recognition of Anglican Orders, but the Orthodox participants at the Union Conference were more hesitant. Within Old Catholic circles themselves the question of the validity of Anglican Orders proved to be the main hindrance to further agreement. This remained an issue until 1931 when a conclusive agreement was finally reached.
The Bonn Union Conferences provoked varying reactions in the Church of England: for the evangelical wing of the Anglican Church they were too Catholic and the anglo-catholics on the other hand feared that a closer relationship with Old Catholics could hinder closer relations with Rome. Moreover, there was a general consensus that the Conference was conceding too much to the Orthodox (in particular in the question of the filioque). The strident reactions of anglo-catholics in the press, like that of Edward Bouverie Pusey, led to Döllinger’s decision not to call a third Union Conference. Nevertheless the conversations at the Bonn Union Conferences made it clear to everyone that Old Catholics, Anglicans (and the Orthodox!) have distinct theological commonalities in spite of their different historical backgrounds.
Development of Relations until 1925
Between 1870 and 1880 Anglican – Old Catholic relations were characterized by a mutual interest in and good will for each other. The Old Catholic Bishop of Switzerland, Eduard Herzog, proclaimed ecclesial fellowship with the Anglican Church of Scotland and the American Episcopal Church in 1879/80.
In 1878 the Lambeth Conference of all Anglican diocesan Bishops expressed its sympathy with Old Catholic endeavors: “We greet with joy every effort towards reform which is based on patterns of the early church. We do not demand strict uniformity and we desire no unnecessary separations.” 
In 1883 the German Synod welcomed all members of the Church of England to receive Holy Communion in both kinds (i.e. bread and wine) in Old Catholic parishes.
In spite of such efforts to establish contacts there were also setbacks. Along with these closer relations there was also some stagnation: The Old Catholic Church of the Netherlands was more reticent in pursuing closer relations with Anglicans and did not accept the validity of Anglican Orders. This led to putting union plans on the back burner. After the Old Catholic Bishops self-organized into the Union of Utrecht in 1889, important issues and questions such as this could only be dealt with by the whole Union.
In 1888 the Lambeth Conference committed Anglicans to encouraging friendly relations with the Old Catholic Churches of Germany and Switzerland. In addition it also extended eucharistic fellowship to Old Catholics under the same prerequisites as communicants of Anglican Churches. This was in recognition of the “willingness the Old Catholics have shown to extend spiritual benefits to members of our own Churches.” 
Even more important than this decision was the promulgation of the so-called “Lambeth Quadrilateral” by the Lambeth Conference, which expressed the position of the Anglican Church with regard to questions of reunification. These four things serve as a basis for reunification: the Holy Scriptures of the Old and New Testament, the Apostles’ Creed and the Nicene Creed, the sacraments of Baptism and the Eucharist, as well as the historic Episcopate.
This Quadrilateral also contains what Old Catholics consider to be the basic elements of the catholicity of the Church: the Church, standing on the foundation of scripture, is Catholic in its teaching (through a recognition of both ecumenical creeds), in its worship (the celebration of the sacraments, in particular Baptism and the Eucharist, being central to the Church’s activity) and in maintaining the historic Episcopate. These four elements are implicitly meant whenever the Bonn Agreement mentions “catholicity.”
If churches are to attain greater unity with each other, then it cannot remain a matter for deliberation in theological studies or bishops’ conferences alone, but rather needs the support of the whole church. In this regard the Anglo-Continental Society in England was seminal in translating Old Catholic theological tracts and making them available to a larger public throughout the 1870’s. In 1908 the “Society of St. Willibrord” was founded in England. Its task was to encourage and facilitate parochial contacts and thus increase mutual knowledge and understanding between Anglicans and Old Catholics at the grassroots level. Today Willibrord Societies are active in many different countries.
Finally an important further step was taken in the year 1925. The Old Catholic Church of the Netherlands declared “without any reservations that Apostolic Succession was not interrupted in the Church of England.” 
This declaration eliminated the last barrier and the International Old Catholic Bishops’ Conference expressed its “hope for a future closer fellowship with the Church of England and its affiliated Churches on a truly Catholic foundation.” 
Five years later the Lambeth Conference also affirmed its desire for “a reunification with Old Catholics.” 
The Bonn Agreement of 1931
On July 2, 1931, the eight members of the Anglican delegation appointed by the Lambeth Conference met with four representatives of the Old Catholic Churches in Bonn.  During the morning time was allotted for mutual questioning: Old Catholics asked Anglicans, among other things, about the authority of the Lambeth Conference and the theological status of the Thirty-Nine Articles in the Anglican Church and the Anglicans asked the Old Catholics about their understanding of the authority of scripture and their theology of the Eucharist. In the afternoon a draft was presented and discussed and the three statements were accepted which we know as the “Bonn Agreement:”
- Each Communion recognizes the catholicity and independence of the other and maintains its own.
- Each Communion agrees to admit members of the other Communion to participate in the Sacraments.
- Intercommunion does not require from either Communion the acceptance of all doctrinal opinion, sacramental devotion or liturgical practice characteristic of the other, but implies that each believes the other to hold all essentials of the Christian Faith. 
On September 7, 1931, the International Old Catholic Bishops’ Conference accepted this agreement for inter-communion and on January 20 and 21, 1932 the Convocations of Canterbury and York ratified the agreement. In the following years all of the Anglican provinces followed the example of the Church of England.
The concept of “inter-communion” used in 1931 was changed to “full communion” in 1961 in conformity with the standardization of ecumenical terminology established at the third World Conference of Faith and Order held at Lund in 1952.
From a contemporary point of view the most important characteristics of this agreement are as follows. First, the recognition of the other Church as Catholic and the concentration on essentials. Second, the understanding that being Catholic does not imply uniformity, but rather that a variety of riches shows the fullness of faith. Third, the insight that eccesial fellowship is crystallized in the celebration of the sacraments, particularly in the Holy Eucharist. Through the reception of the Body of Christ we become ever anew the Body of Christ. In 1981 the reformed ecumenical theologian Lukas Vischer referred to the implicit ecclesiology of the Bonn Agreement in a festive lecture celebrating its 50th anniversary: the Church is understood as Eucharistic fellowship, under the leadership of the office of the bishop, which helps “every single local church to be unified in its life and witness and, at the same time, facilitating the common life and witness of all local churches in an all-embracing conciliar fellowship.” 
In hindsight and on the basis of later ecumenical agreements some critical remarks are in order. First, the Bonn Agreement does not contain any “directives for implementation” regarding how the agreement can be incarnated in the life of both churches; secondly, there are no considerations of non-theological factors (e.g. linguistic and cultural differences), which play an important role in putting the agreement into practice; and thirdly, although it is a declaration of mutual recognition and acknowledgement of the legitimate “being” of the other church, there are no challenges concerning the future common life and witness of the two churches. A vision of the Church – according to Lukas Vischer in 1981 – is missing in the Bonn Agreement. The Agreement does not constitute a “Communion.” Following the Agreement both churches still do not behave as though they were “one fellowship of local churches.” 
Developments from 1931 to Today
During the Third Reich it became very difficult to maintain relations; in some instances it was practically impossible. Following the Second World War and stemming from a increased presence of British and American Anglicans who came into the country as the occupying powers, new relations between Anglicans and Old Catholics were established from place to place. Since the beginning of the 1950’s Old Catholic parishes support Anglican missionary and development projects with money and materials.
In 1965 the Bonn Agreement was extended by the Old Catholics to include the Philippine Independent Church, the Reformed Episcopal Church of Spain and the Lusitanian Catholic Apostolic Evangelical Church of Portugal.
Again and again, however, the relations were strained. The difficulties came about for different reasons, not the least of which was the fact that the Bonn Agreement, after establishing a fundamental theological consensus, failed to offer suggestions for filling the agreement with life in a practical sense. We have had to learn from experience that it is good mutually to consult or inform one another about internal developments.
From 1957 to 1993 the Anglican – Old Catholic Theological Conference, held regularly on specific themes, provided for an exchange of theological ideas. For several years in the 1990’s organized gatherings of young Old Catholic and Anglican theologians took place. In the summer of 2005 and in preparation for the 75th anniversary of the Bonn Agreement a bilateral conference was held in Leeds (England) on the theme “Anglican and Old Catholic Ecclesiologies: On the Way to Further Convergence.” 
In 1998 the Archbishops of Canterbury and Utrecht founded the “Anglican – Old Catholic International Coordinating Council” (AOCICC). It is the task of this council to discover how and in what ways an increased cooperation is possible. In pursuing that goal the members of the council inform each other at annual gatherings about on-going developments in their respective jurisdictions. They also exchange information about the status of ecumenical relations to other churches. In addition recommendations about continuing cooperation emerge in deliberation and are forwarded to the respective churches. Initially the Council was given a mandate for five years; since 2005 the council continues its work in a new configuration and with a new mandate. New emphasis is being placed on dealing with ecclesiological issues as well as on encouraging more cooperation between neighboring Anglican and Old Catholic parishes in Europe.
These and other issues are in deliberation, whether in the AOCICC or at gatherings of European Old Catholic and Anglican bishops which now take place regularly. A central issue currently concerns the form of a common witness of Old Catholics and Anglicans in Europe. Trust is the foundation of all cooperation. That foundation has already been established in the Bonn Agreement: trust that the other church in all its distinctness and sometimes even its strangeness lives out its catholicity. Old Catholics and Anglicans have much to give each other – theologically, spiritually and practically. Summing up, we might say that the main thing is that we strengthen each other mutually in our catholicity. An essential feature of that is the consciousness that being Catholic always involves reform and renewal. In this endeavor we can and should be a critical corrective for each other. True siblinghood is not revealed in mutual admiration, but rather in loving criticism and in an openness infused with affection.
Our cooperation is espressed in our joint celebration of worship (usually Eucharistic worship) as our common witness; it is also expressed in the sharing of charismas and gifts, as churches and as individuals. We have become more conscious over the last decades that our mutual ministry not only can grow but needs to grow. Part of that includes dealing with the difficult issues of overlapping jurisdictions in continental Europe. (Along side the Old Catholic jurisdictions there are four Anglican jurisdictions in continental Europe: the Diocese of the Church of England, the Convocation of American Churches in Europe, the Portuguese-Lusitanian and Spanish Church.) Concretely our mutual ministry is realized in many ways: at the episcopal level in the participation of bishops in the consecration of bishops in the other church, in participation in the Confirmation services of the sister church or in common consultations; at the priestly/parochial level there is mutual assistance in pastoral emergencies, in supplying for each other during vacancies and in participation in each others’ pastoral conferences. In addition we should not forget the good contacts and friendships, which develop between individuals and parishes as well as in the shared use of church buildings or in special events organized together. The official International Celebration of the 75th Jubilee of the Bonn Agreement took place on August 9, 2006 in Freiburg with the participation of the Archbishop of Canterbury and the Archbishop of Utrecht. The time-tested tradition of participation of Anglicans in Old Catholic Congresses was renewed. The theme of the Congress, “Hope, which Lives in Us: Old Catholics and Anglicans in Europe,” shows clearly that former Anglican guests have long ago become good acquaintances, friends and sisters and brothers. The common celebration of the Holy Eucharist as well as the presentations of Archbishop Dr. Rowan Williams and Archbishop Dr. Joris Vercammen and the concluding forum discussions brought many new impulses for our mutual ministry in the future. At the end of the Congress a communiqué was issued which commemorates the fact that Anglicans and Old Catholics have come closer and closer together since 1931 “through theological reflection, practical cooperation locally but also through other factors like migration and meeting social challenges.” For that reason the Congress called for “a deepening of that same fellowship between the two churches as experienced at the Congress on all levels of the parishes with the active participation of lay people.” 
Author: Rev. Prof. Dr. Angela Berlis, Bern (abridged text)
Translator: Rev. Daniel G. Conklin, Berlin
 Cf. Angela Berlin, Frauen im Prozeß der Kirchwerdung. Eine historisch-theologische Studie zur Anfangsphase des deutschen Altkatholizismus, Frankfurt a.M. 1998. Due to limited space a discussion of Anglican interest in the Church of Utrecht is not possible. Cf. John Mason Neale, A History of the So-Called Jansenist Church of Holland, Oxford, 1858.
 As expressed by Victor Conzemius, quoted in Peter Neuner, Döllinger als Theologe der Ökumene, Paderborn, 1979, 178.
 Cf. Heinrich Reusch (Ed.), Bericht über die 1874 und 1875 zu Bonn gehaltenen Unions-Conferenzen. Neudruck der Ausgabe in zwei Bänden von 1874 und 1875, (Schriftenreihe des Altkatholischen Seminars der Universität Bonn, Reihe A,2; cf. also Neuner, Op. Cit.)
 Citation of the Declaration in Küry, Die Altkatholische Kirche, 466.
 Citation of the Declaration in Küry, Die Altkatholische Kirche, 467.
 Citation of the Declaration in Küry, Die Altkatholische Kirche, 468. We cannot delve into the background of this change of stance. It took place within the context of an ecclesiastical and theological renewal of the Old Catholic Church of the Netherlands at the end of the 19th century.
 Citation of the Declaration in Küry, Ibid.
 Cited by Frei, Die altkatholisch-anglikanische Vereinbarung, 215.
 Citation of the Minutes of the Union Conference of July 2, 1931 in Bonn in Küry, Op. Cit., 468-478.
 Citation of the text in Ibid. 477f.; Harding Meyer, Hans Jörg Urban, Lukas Vischer (Ed.), Dokumente wachsender Übereinstimmung. Sämtliche Berichte und Konsenstexte interkonfessioneller Gespräche auf Weltebene 1931-1981, Bd. I, Paderborn – Frankfurt, 1983, 77-79.
 Lukas Vischer, Das Bonner Abkommen von 1931 im Lichte der ökumenischen Bewegung, in IKZ 71 (1981), 237-253, here 240.
 Ibid., 248f., here 249.
 The contributions of this conference were published in a special issue of the IKZ in 2007.
 Christen Heute, Zeitschrift der Altkatholiken 50 (2006), 224.