In A Liminal Church: Refugees, Conversions and the Latin Diocese of Jerusalem, Maria Chiara Rioli builds upon a growing historiography which has examined the transnational Roman Catholic relationship to postwar Palestine and the wider Middle East. Themes in this body of work have included the Vatican's response to the rise of political Zionism and the State of Israel, its attempts to protect its institutional and spiritual autonomy in the midst of expanding Arab-Jewish conflict, and the Church's efforts to address the expanding postwar refugee crisis, particularly among Arab Christians in the region.

Rioli's unique contribution to this scholarship is to examine these wider tensions through the lens of the Latin Diocese of Jerusalem, a Patriarchate which oversaw Latin Catholicism in Palestine (and later Israel), Jordan, and Cyprus. What emerges from this approach is the history of a diocese which functioned both as a regional nerve center for wider Catholic visions for the region and as a repository of a diverse and sometimes conflicting set of political, ideological, and liturgical impulses. At the center of Rioli's work are both the convergences and the divergences between the Roman center and the diocesan periphery, set against the backdrop of tensions between various Christian rites, the interests of regional and international political actors, and ancestral discord between Christians, Jews, and Muslims.

Chief among the common concerns of papal Rome and the Patriarchate was the preservation of the Church's institutional presence in the region (which had expanded rapidly since the 19th century) and the protection of the indigenous Catholic population, the “living stones” of the faith in the Holy Land. Rioli traces the Vatican's reticence to both Zionism and Arab nationalism, movements which Patriarchs Luigi Barlassina (1920–1947) and Alberto Gori (1949–1970) also considered a threat to the Church's autonomy in the very heartland of the Christian faith. The Patriarchate was supported in this by a variety of international Catholic organizations, including the Franciscan Custody of the Holy Land, the Assumptionists, the Benedictines, the Pontifical Mission for Palestine, and the New York-based Catholic Near East Welfare Association (CNEWA). Rioli traces the intriguing diplomatic work of the CNEWA's head, Msgr. Thomas McMahon, who worked closely with Barlassina and Gori to coordinate Catholic aid efforts in the region, and who functioned as a de facto envoy of the Vatican vis-à-vis Israel, Jordan, and Egypt. In this way, Rioli presents the Latin Diocese of Jerusalem as the regional locus of a transnational Roman Catholic network which expressed broad solidarity on questions of Catholic institutional autonomy in the region, the internationalization of the Holy Places, and the right of return for Catholic refugees displaced by the Arab-Israeli War.

The most interesting and novel aspect of Rioli's study, however, is its illumination of the various points of friction between the Holy See and the Latin Diocese. The idea of a Church that functioned as a rigid, transnational monolith is clearly dispelled here. Rioli presents the case of the Association of Saint James (ASJ), which emerged within the context of the nascent Catholic-Jewish ecumenism of the postwar decade. Inspired in part by the 1947 Seelisberg Conference, which saw Jewish and Christian (including Catholic) delegates discuss the context and origins of Christian anti-Semitism and also by the postwar ecumenical activism of figures such as Jacques Maritain, Jules Isaac, and Charles Journet, the ASJ facilitated the conversion of Israeli Jews to Catholicism in the ecumenical spirit of Seelisberg and broader postwar ecumenism. Established in 1955 and named for the apostle James (the first bishop of Jerusalem in the biblical tradition), the association sought to create converts who would function as a bridge linking Catholicism and Judaism both culturally and theologically. Significantly, the ASJ was created with the explicit approval of the Holy See's Congregation for the Oriental Church. Its head, Cardinal Eugene Tisserant, envisioned the ASJ as a vehicle for Catholic-Jewish fellowship and as a means of facilitating smoother postwar relations between the Holy See and the State of Israel. Rioli traces here the growing tensions between Rome and the Latin Diocese of Jerusalem, where catechumens and converts were not regarded as ecumenical links to Judaism, and where attitudes toward Zionism remained largely rooted in ancestral Catholic anti-Judaism and lingering fears of Judeo-Bolshevism. Gori attempted to steer the Latin Diocese between the nascent ecumenical impulses emerging from Rome (which included closer cooperation between the Latin and Melkite rites), the Israeli state's ongoing apprehensions about the “right of return” of Arab Christian refugees, and the legal and educational rights of Jewish converts to Catholicism. It was an onerous balancing act, which Rioli capably illuminates.

For this work, Rioli has drawn upon an impressive array of Israeli, European, and American archival sources, which adds to its depth of analysis. Particularly engaging was her examination of the ecumenical initiatives of the ASJ, a subject which deserves its own book-length treatment. In sum, this is a rigorous and rich study which skillfully situates the Latin Diocese of Jerusalem within the complex kaleidoscope of postwar relations between the Vatican, Palestine, Israel, and Jordan. Scholars interested in the complexities of the postwar transnational Catholic Church, the Middle East in the early Cold War, interfaith relations, and Catholic-Jewish ecumenism can read this work with profit.