Precursors: Black church and spirituals, preachers as leaders, Dr. King as example; coming of Zen Buddhism to SF in Fifties. Both these traditions had two sides. First, the problem of passivity (freedom in the afterlife, freedom by detachment from suffering) on the other hand, engagement in social justice (Jesus as symbol of poor, the peacemaker, the Hebrews in slavery under the pharaoh; buddhism as compassion with suffering, rejection of material values, etc.).
The Catholic church joined this stirring in the late 50s culminating in 1962, the year of Port Huron, the time of the Second Vatican Council and Pope John XXIII - Michael Novick - to be a Catholic now meant to believe more or less anything one wished to believe, or at least in the sense in which one personally interpreted it. One could be a Catholic 'in spirit'. One could take Catholic to mean the 'culture' in which one was born, rather than to mean a creed making objective and rigorous demands. One could imagine Rome as a distant and irrelevant anachronism, embarrassment, even adversary. Rome as 'them'." Such views of the Second Vatican Council were condemned by the Church's hierarchy, and the works of theologians who were active in the Council or who closely adhered to the Council's aspect of reform (such as Hans Küng) have often been criticized by the Church for espousing a belief system that is radical and misguided.
1960 –62. While SNCC and SDS are interpreted as being secular, the evidence is that many of the founders were graduates of theological schools. James Lawson, John Lewis. Invariably the local leaders were clergy, the meeting locations were churches. King was a Baptist. [they were from the activist current, social gospel]. As for sds, Casey Hayden belonged to an integrated Christian existentialist community, Maria Varela was a staff member of Young Christian Students, Jim Monsonis was director of a national student christian organization.
We were influenced by Ignacio Silone and Albert Camus (pp. 152, Long Sixties)
The mainstream of the civil rights movement was mainly Christian but also ecumenical. Protestant leaders were there as National Council of Churches. Jewish rabbis and leaders mainly from Reform Judaism. Gandhi’s philosophy of a “soul force” and nonviolence as a way of life strongly influenced Lawson, Dr. King, and Bayard Rustin, the organizer of the 1963 March on Washington, among many others. Malcolm X is credited with leading the Nation of Islam into active support of desegregation and black power, recruiting many Muslims who were victims of mass incarceration. Malcolm before his death would evolve in an ecumenical direction, after taking a pilgrimage to Mecca and parts of Africa, where he saw people of many different colors in the Islamic faith.
An indispensible support group for the UFW was the Catholic clergy, but also an ecumenical coalition. Masses were common in the fields, marches like the 1966 Delano march were cast in spiritual terms - the encampment before crossing the Sacramento River to the Promised Land.
When the Vietnam war escalated, many traditional religious groups were in the forefront of the opposition, starting with the Quakers [American Friends Service Committee] and many followers inspired by Gandhi’s nonviolent beliefs. The Catholic Workers [Dorothy Day] introduced notions of voluntary simplicity and standing with the poor, as well as war resistance. The most prominent religious force in the peace movement was that of the Berrigan brothers, Philip and Daniel, two priests who committed continual acts of civil disobedience, and a Catholic underground network that poured blood on draft files, supported the burning of draft cards, etc.
In Vietnam itself, while the revolution was organized and led by Communists and nationalists, much of the spiritual force came from Buddhist monks who opposed violence and foreign intervention, while sometimes immolating themselves to draw the attention of the world to Vietnamese suffering.
Once again, The context is important here, lest you believe that the religious institutions were behind the social movements of the Sixties. They were not. Again and again, the hierarchy of the religious institutions was on the side of the state, the military and corporate power. King’s most famous essay, the “letter from a Birmingham jail”  castigated the Southern white churches, especially those professing to be moderate, for being part of the racial status quo. As noted, King himself was a controversial figure in the Southern Baptist Church. It was the Catholic hierarchy which lobbied hardest for military intervention in Vietnam, where 10 percent of the population was Catholic as a result of the century of French colonialism. Not only was the Church protecting its own, but it led the Cold War anti-communist campaign against communism on the theological grounds that it was “godless.”
I want to concentrate today on the sociology of this theology, if you will, and its history. See chapters 19, 20, 21, pp 150-167, which cover the topics of Liberation Theology, Black Liberation Theology, and the Spirituality of the Counterculture.
Excellent work has been done on this subject by Christian Smith [The Emergence of Liberation Theology, Radical Religion and Social Movement Theory, University of Chicago, 1991] and Harvey Cox at Harvard.
The context here is the Second Vatican Council “opening” and the revolutionary movements developing in Latin and Central America in the 1960s. The Cuban Revolution  inspired at least 20 more revolutionary guerrilla movements and a brutal counter-movement [Operation Condor] involving death squads and US trainers. None of these guerrilla movements succeeded in taking power, although many of their participants later came to power through elections [Dilma Roussef in Brazil, Hugo Chavez in Venezuela, the Uruguayan leadership, the brother of Mauricio Funes in El Salvador, Daniel Ortega in Nicaragua etc] These movements were largely secular, nationalist and marxist, although all of them had religious roots as well. The Vatican, as well as the US, was alarmed at the emergence of these non-Catholic, or atheist, movements. They were a reminder of the French and Mexican republican revolutions in which the clerics as well as the oligarchs were driven out of power.
In response to these Cuban-inspired movements, the US under Kennedy launched the Green Berets but also the Peace Corps, a two track approach to hunting down guerrillas while offering assistance to poor communities.
The revolutions also helped inspire a new commitment in circles of the Catholic church to fashioning an approach that became known as liberation theology. There were two streams, young theologians trained in Europe, and theologians already in Latin America [Peru’s Gustavo Guttierez, Brazil’s Dom Helder Camera, Leonardo and Clodovis Boff in Brazil. Also Samuel Ruiz in Chiapas. Bishop Oscar Romero in El Salvador] Unlike the Marxists, these were people who believed in the “historical Jesus”, who served the poor and opposed the taxes and soldiers of the Roman empire. They co-existed with Marxism, which added to the threat they posed to the Church hierarchy.
One thousand were excommunicated, silenced, kidnapped, tortured or killed over three decades.
Their method was to form “base communities” not unlike sds or sncc community organizing projects, although religious in nature. They developed a doctrine of affirmative action, known as the Special Preference for the Poor, which meant a belief that this historical Jesus sympathized and identified most with the demonized, exploited and impoverished.
They translated the New Testament into spanish and indigenous languages, and formed discussion groups in the base communities. This was a huge shift from the top down Church and extremely empowering for the peasants and indigenous. Perhaps as many as 200,000 base communities by 1970. In Chiapas in 1974 there was a convention held in 4 Mayan languages, recalling the the founder of the movement St. Bartolomew de las Casas, the bishop of Chiapas who became a supporter of the indigenous against the Spanish crown and Christopher Columbus. [his cathedral is in Chiapas today].
In 1968 – the year of global revolutions – liberation theology was formally accepted as doctrine at a meeting of 130 Latin American bishops meeting at Medellin, Colombia. See p. 153. The bishops called for “active, creative and decisive participation in the construction of a new society.” Participatory democracy and liberation theology were intertwined.
The doctrine remained in place for a decade. Priests played major roles in 1979 Nicaraguan revolution and the insurgency in El Salvador, among other places.
The counter-movement of Vatican-Latin Amercan church hierarchies-and states was fierce. Not only counterterrorism and imposition of dictatorships [for example in Chile, 1973] but a counter-movement against the doctrine of liberation theology itself. At Right-wing Opus Dei rose to power. beginning of Reagan era, State Dept task force issued the “Santa Fe Declaration” defining liberation theology as contrary to American national security. Reagan very close to Vatican. Pope John Paul denounced priests working with the Sandinistas [Gioconda Belli was there]. Leonardo Boff silenced. Oscar Romero and American nuns murdered in El Salvador. Bishop Ruiz would be replaced in Chiapas. The pope attacked those who depicted Jesus as a political activist who fought the empire and was involved in class struggle. [p. 154]
Central figure in the counter-movement was Joseph Ratzinger, a German theologian who strongly opposed feminists and the new left at the university in 1969, and who forced abortion counseling centers to close. He was chief officer of the Office of the Inquisition, now renamed the Congregation for the Doctrine of the Faith. He argued in 1994 that Catholic American voters were cooperating with Evil if they voted for John Kerry for president, because of kerry’s pro-choice views. Kerry lost in part because of the Catholic vote in Ohio, Iowa and New Mexico.
Ratzinger is now Pope Benedict XIV. The approved structures of liberation theology have been dismantled and the Church has shifted to the right. But the base communities remain and liberation theology is still a major current in Latin America.
Liberation theology also inspired parallel spiritual awakenings: feminist liberation theology, eco-theology etc, in the decades since. One of those has been Black Liberation Theology, chapter 20, pp. 155.