Humanae vitae is an encyclical written by Pope Paul VI and dated 25 July 1968. The text was issued at a Vatican press conference on 29 July. Subtitled On the Regulation of Birth, it re-affirmed the teaching of the Catholic Church regarding married love, responsible parenthood, and the rejection of artificial contraception. In formulating his teaching he explained why he did not accept the conclusions of the Pontifical Commission on Birth Control established by his predecessor, Pope John XXIII, a commission he himself had expanded.

Pope Paul VI was head of the Catholic Church and sovereign of the Vatican City State from 21 June 1963 to his death in 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.