Christian feast day: Luke Loan Ba Vu (Roman Catholic Church)

Vietnamese Martyrs, also known as the Martyrs of Tonkin and Cochinchina, collectively Martyrs of Annam or formerly Martyrs of Indochina, are saints of the Catholic Church who were canonized by Pope John Paul II. On June 19, 1988, thousands of overseas Vietnamese worldwide gathered at St. Peter's Square for the celebration of the canonization of 117 Vietnamese Martyrs, an event organized by Monsignor Trần Văn Hoài. Their memorial in the current General Roman Calendar is on November 24 as Saint Andrew Dung-Lac and Companions, although many of these saints have a second memorial, having been beatified and inscribed on the local calendar prior to the canonization of the group.

The Catholic Church, also known as the Roman Catholic Church, is the largest Christian church, with 1.27 to 1.41 billion baptized Catholics worldwide as of 2025. It is among the world's oldest and largest international institutions and has played a prominent role in the history and development of Western civilization. The Church consists of 24 sui iuris (autonomous) churches, including the Latin Church and 23 Eastern Catholic Churches, which comprise almost 3,500 dioceses and eparchies around the world, each overseen by one or more bishops. The pope, who is the bishop of Rome, is the chief pastor of the church.

June 5 is the 156th day of the year in the Gregorian calendar; 209 days remain until the end of the year.