Recorded history of Catholicism in Vietnam was as the followings: According to the Royal Vietnamese Annals: “in the year of Nguyên Hòa (1533), under the reign of King Lê Trang Tông, there was a decree already in existence that banned Christianity. The decree mentioned the name of an European individual, Ignatio, who by seaway had landed and preached the religion at Ninh Cường and Quỳnh Anh Villages, district Nam Chân” (present Nam Định). The document did not mention his congregation, but probably Ignatio belonged to a religious order. Based on the fact that the above decree had been issued before 1533 it is understandable to presume that the Good News of Jesus Christ had been preached before that year of 1533 on the soil of Vietnam. Therefore, it was a very important year in the history of the Vietnamese Catholic Church.
In the very early stage of the Vietnamese Church, the missionaries traveled all over the country. They came from different European countries via neighboring countries such as the Philippine Islands, Malacca, Macao, Japan,... They were accompanied by European merchants and belonged to a variety of congregations:Society of Jesus (SJ)Dominican Fathers (OP), Order of the Minor Friars of St. Francis (Franciscans, ofm) and the Foreign Mission of Paris (MEP).
Link (here) to great link on the history of the Catholic Church In Vietnam
Link (here) to an article about recent Jesuit history in Vietnam.