The Apostolic Union of Secular Priests is an association of Roman Catholic secular priests (i.e. priests who are not monastics and do not belong to any religious institute).
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It was founded in the seventeenth century by the Venerable Bartholomew Holzhauser. In 1903, Pope Pius X placed the union under his special protection. In 1913, it was reorganized in France by Canon Lebeurier.
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Apostolic Union of Secular Priests Wikipedia(Text) CC BY-SA