John XXIII in the context of "Pope Pius XII"

Pope Paul VI (born Giovanni Battista Enrico Antonio Maria Montini; 26 September 1897 – 6 August 1978) was head of the Catholic Church and sovereign of the Vatican City State from 21 June 1963 until his death on 6 August 1978. Succeeding John XXIII, he continued the Second Vatican Council, which he closed in 1965, implementing its numerous reforms. He fostered improved ecumenical relations with Eastern Orthodox and Protestant churches, which resulted in many historic meetings and agreements. In January 1964, he flew to Jordan, the first time a reigning pontiff had left Italy in more than a century.

Montini served in the Holy See's Secretariat of State from 1922 to 1954, and along with Domenico Tardini was considered the closest and most influential advisor of Pope Pius XII. In 1954, Pius named Montini Archbishop of Milan, the largest Italian diocese. Montini later became the Secretary of the Italian Bishops' Conference. John XXIII elevated Montini to the College of Cardinals in 1958, and after his death, Montini was, with little to no opposition, elected his successor, taking the name Paul VI.

Aggiornamento (Italian pronunciation: [addʒornaˈmento]) is an Italian word meaning "bringing up to date", "updating". It was made famous by Pope John XXIII, and was one of the key words at the Second Vatican Council, used by both bishops and the media.

Rerum novarum, or Rights and Duties of Capital and Labor, is an encyclical issued by Pope Leo XIII on 15 May 1891. It is an open letter, passed to all Catholic patriarchs, primates, archbishops, and bishops, which addressed the condition of the working class. It discusses the relationships and mutual duties between labor and capital, as well as government and its citizens. Of primary concern is the need for poverty amelioration of the working class. It supports the rights of labor to form trade unions, and rejects socialism and laissez-faire capitalism, or unregulated, brutal capitalism, while affirming the right to private property and to a living wage.

A foundational text of modern Catholic social teaching, many of the positions in Rerum novarum are supplemented by later encyclicals, in particular Pius XI's Quadragesimo anno (1931), John XXIII's Mater et magistra (1961), Paul VI's Octogesima adveniens (1971), and John Paul II's Centesimus annus (1991), each of which commemorates an anniversary of the publication of Rerum novarum. It also inspired Catholic activism, and influenced distributists and supporters of corporatism. Socialists generally contest the encyclical's interpretation of socialism, and some socialists, particularly Catholic socialists, interpret Rerum novarum as not rejecting socialism, argue that divine law justifies the abolition of private property, and emphasize its anti-capitalist character.

Pope John Paul I (born Albino Luciani; 17 October 1912 – 28 September 1978) was head of the Catholic Church and sovereign of the Vatican City from 26 August 1978 until his death 33 days later. His reign is among the shortest in papal history, giving rise to the most recent year of three popes—the first since 1605. John Paul I remains the most recent Italian-born pope, the last in a succession of such popes that started with Clement VII in 1523. He was also the first pope to have been born in the 20th century.

Before the August 1978 papal conclave that elected him, he expressed his desire not to be elected, telling those close to him that he would decline the papacy if elected, but despite this, upon the cardinals' electing him, he felt an obligation to accept. He was the first pontiff to have a double name, choosing "John Paul" in honour of his two immediate predecessors, John XXIII and Paul VI. He explained that he was indebted to John XXIII and to Paul VI for naming him a bishop and a cardinal, respectively. Furthermore, he was the only pope to add the ordinal number "I" to his papal name when choosing it. It was reported by Catholic media that John Paul was not aware at the time that this was unusual.