The Crosiers were founded by five men attached to the household of the prince-bishop of Liege, Rudolf of Zähringen, who accompanied the Emperor Frederick Barbarossa on the Third Crusade (1189–1191).

Upon their return, the five, led by Theodorus de Cellis (1166–1236),[5] sought a new way of life, and shortly before his death, their bishop appointed them to be canons of his St. Lambert's Cathedral, Liège.

Only one of their five founders for whom they have a name is the group's leader, and that only in its Latin form, Theodoricus (or Diederick)[6] de Cellis, which first appears in a short history of the Order published in 1636.

[6] There is no record of the presence of the Crosiers at Huy until the 1240s, and only in 1322 did Clairlieu become the site of a magnificent church dedicated to the Holy Cross instead of the small chapel of St. Theobald.

[8] Because they were established in the early 13th century, they were contemporaries of the Dominicans and Franciscans, they were frequently misidentified as friars and were often confused with other religious orders known as Crosiers who identified themselves with the Holy Cross.

So, for example, there was a very old tradition that Bishop Albert of Prague took several Crosiers with him to Livonia, but these were in fact members of the Bohemian order of the Holy Cross.

In England, too, they and an Italian order of the Holy Cross were both identified as Crutched Friars, and so the location of their houses and their activities are often mistaken for each other.

[citation needed] One tradition claims that Theodorus de Cellis assisted St. Dominic in his preaching to the Albigenses of southern France;[8] a Crosier presence in that area is reliably recorded from early in their history.

They seemed likewise doomed to extinction by the decree of King William I of the Netherlands, which forbade religious houses in his realm to admit novices.

In second half of the 19th century, the Crosiers returned to their Belgian birthplace, and even made an effort to transplant the Order outside Europe to the United States when their Master General sent some members to Bay Settlement, Wisconsin, in 1857.

She is said to have appeared to a lay brother of the Order, John Novelan, in the Paris house in 1287 and to have instructed him to go to Cologne and exhume her relics from under a pear tree in the garden of one Arnulf, a prominent burger of that city.

After some disbelief and resistance on the part of his superiors, Brother John fulfilled the saint's directions and brought her relics to the motherhouse at Huy on 18 July.