[1][2] The Fœderatio Internationalis Una Voce (or FIUV) was founded on December 19, 1964 in Paris by Georges Cerbelaud-Salagnac in order to promote the Tridentine Mass from the Pre-Vatican II Missale Romanum (1962).

[3][5][9] FIUV members value the traditional Latin Mass as direct link with the early Church and for conveying the mystery and majesty of God,[10][11] but have been critiqued for elitism and for its emphasis on private religious devotion.

[14][15] The organization's influence at the highest levels of the Vatican has led to the authorization of the Tridentine Mass without specific permission or indult by local bishops, and the wider implementation of the motu proprio, Summorum Pontificum.

[3][11][16] The International Federation represents 42 member associations in Argentina, Australia, Austria, Belarus, Belgium, Brazil, Canada, Chile, Costa Rica, Colombia, Croatia, Cuba, Czech Republic, England and Wales, Estonia, Finland, France, Germany, India, Ireland, Italy, Japan, Latvia, Malta, Mexico, the Netherlands, New Zealand, Nigeria, Norway, Peru, the Philippines, Poland, Portugal, Puerto Rico, Russia, Scotland, Singapore, South Africa, Spain, Switzerland, Taiwan, Ukraine and the USA.

Requests for information and assistance have come from Denmark, Honduras, Hungary, Indonesia, Kenya, Korea, Lithuania, Luxembourg, Panama, Sarawak (Malaysian Borneo) and Slovenia.