But his parents, Jean Fallize and Thérèse Pfeffer, were Luxembourgers from Arsdorf (Luxembourgish: Uerschdref, now a part of the Municipality of Rambrouch), in the canton of Redange.
In 1850, when Jean-Baptiste was six years old, they moved with their children across the border to Harlange (German: Harlingen, Luxembourgish: Harel, now in the municipality of Lac de la Haute-Sûre), in the canton of Wiltz, in the Grand Duchy of Luxembourg.
After graduating in 1866, he accepted the request of Nicolas Adames, the first Bishop of Luxembourg, and went to Rome to study philosophy, theology and other subjects at the Collegium Germanicum et Hungaricum, the German-speaking seminary, and at the Pontifical Gregorian University, the Jesuit school.
Some of his editorials annoyed the Prime Minister, Félix Baron de Blochausen, a Liberal, so much that the priest got thirty days in jail in 1880.
But he also won on 14 June 1881 a seat with the Chamber of Deputies of the Grand Duchy to represent the canton of Clervaux (German: Clerf, Luxembourgish: Klief) in northern Luxembourg.
With characteristic energy and efficiency, Fallize, assisted by a group of priests imported from Luxembourg, set out to organize a Catholic community throughout Norway.
In 1913, he ensured that the Vatican would be the first to recognize the Norwegian sovereignty over Svalbard and added the archipelago's German name, "Spitsbergen", to his episcopal titles.
]"[4] He was a shepherd of the old school, who demanded total obedience in the name of the Church, so he got into conflict with just about everyone – the people, the sisters, the civil authorities and even the Vatican.
23 days later, on 31 May, Pope Pius X made him an Assistant to the Throne of St. Peter and a Papal Count of Rome for his missionary efforts and achievements in growing the Catholic Church in Norway.
Old age and illness were given as the official reasons but one of the biographers believed that his resignation was made at the request of the Vatican, which had found him "a little too willful" and difficult.
Fluent in five languages – German, French, Norwegian, Latin and Dutch, Fallize was more than just an editor and publisher of newspapers and a copywriter for calendars.
He also penned poems, editorials, lectures, reports, memoirs, travelogues but his subjects were not limited to the Catholic Church, Norway and Luxembourg.
[10] When he was in Norway, Johannes Olav wrote long travel stories, which were translated into German, Norwegian and Portuguese, and descriptions of wildlife, cities, villages and landscapes.
[10] He also edited Papal letters and directives in a book, Kirkelige Bekjendtgjørelser [Ecclesiastical Announcements], as well as works of edification and school textbooks.
[10] He also contributed to magazines such as Katholische Missionen in Freiburg im Breisgau, Les missions catholiques in Lyon and St. Olav Katholsk tidende in Christiania.
One of them is Der kleine Jesus als Applicant, a jubilee pamphlet published in Norwegian in 1895 and German in 1898 to encourage the Catholic youth to become priests, monks and nuns.
[10] There is a monument honoring Fallize, with an accompanying chapel, on the spot of the former tannery, where his father once worked, in the valley of the Bëtlerbaach (German: Bettlingenbach), on the Belgian border.