Br JR, I have never heard these facts before anywhere. Can you give some backup for what you are posting?
Here is the actual story of what we know today as the Tridentine Mass taken from the Franciscan archives in Assisi, which date back 800 years to Brother Elias, who founded the archives after the death of the Holy Father Francis.
franciscan-archive.org/liturgicale.html
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St. Francis of Assisi can be rightly regarded as the “savior” of the Ancient Roman Rite, since, at the time of the foundation of his Order, on account of his desire to live the same religious life that the Apostles lived with Christ Jesus, the three years before He was Crucified and Died for our salvation, he petitioned Pope Innocent III to take as the rite of his Order, the ancient Rite of the Roman Church, which was held to be the “Rite of St. Peter the Apostle”. During the reign of Innocent III, this rite was only used on the Feast of the Chair of St. Peter, in the private papal Chapel, for the so-called Gallican Rite was universally employed in the Diocese of Rome. In addition only 3 known copies of the liturgical books of this ancient rite were still extant in 1215, one of which was falling to pieces. Pope Innocent III granted St. Francis’ request and gave him one of the good, still extant copies of the Sacramentum, Lectionary, Rituale and other books.
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A bit off-topic, but as I’ve said before, while I’ve known many religious of various orders and congregations over the years, I’ve had little interaction with Franciscans of any stripe.
That said in preamble, please allow me a few questions:
(1) I have a copy (somewhere) of the pre-conciliar Breviarium Seraphicum OFM Cap. How much does that differ from the OFM beyond the kalendar?
They do not differ at all. The entire Franciscan family uses only one breviary, one missal and one calendar. Our liturgical life is governed by a joint commission known as the Franciscan Liturgical Commission. The Commission presents everything to the Sacred Congregation for Divine Worship before publication. The chief liturgists on the commission come from the 112 branches of the Franciscan family. Only the four Ministers General have the authority to approve the sacred books and calendar before going to the Sacred Congregation for Divine Worship.
The Minister General also define the rubrics for the Franciscan Missal, the EF and the OF used in the Franciscan family. For that reason, you will see things happening or not happening at a mass celebrated by a friar that you would not see at a mass celebrated by a secular priest of one of the ED institutes. They must follow the rubrics as they are in the missal. Friars are not bound by those rubrics for the mass or the breviary. We have our own Ordo for mass and office. The ordo contains the rubrics and the liturgical calendar.
(2) How many other versions exist and how much do they differ beyond the kalendar?
There is only one version of the Seraphic Missal and Breviary. The Seraphic Missal and Breviary was abrogated by Pope Paul VI in 1970, never to be celebrated again. It’s not covered by the SP. SP only covers the Tridentine Mass, which was never abrogated. Our mass was abrogated. Pope Benedict has not resurrected it.
(3) I presume that the Caps had one, but just how many versions were there of the Missale Seraphicum and how do they differ from one another, again, beyond the kalendar?
Because we are one family with one father, we have only one missal. More than one would violate Franciscan Succession. It is very important to protect the succession. The differences are going to be by regions and by individual houses, not by obediences. All of the obediences used the same books. For example, the Americans were much closer to the secular than were the Europeans, because the Church in the USA was run by secular clergy. Most friars grew up in secular run parishes and were taught by sisters who knew nothing about the Franciscan liturgical tradition. When these men entered any of the Franciscan obediences, they brought with them their American Secular Catholic liturgical customs. These blended with the Franciscan customs. You could see this in little things like kneeling during the consecration or kneeling at the communion rail. This was not done in the European regions that were governed by regular bishops instead of secular bishops. We’ve always had few regular clergy in the USA.
(4) Assuming that they weren’t all destroyed in the post-conciliar purge, where might I get a copy of one? Perhaps you have a link to an on-line PDF?
They were not destroyed and they are not available to the public. Only a male Franciscan can get his hands on one. They are very rare, because they were not printed after the late 1960s. Most communities of sisters gave them away. The friars kept theirs. They are usually kept at motherhouses, novitiates, formation houses and theologate libraries. We have one in our small community. It is under lock and key in my cell. If they are damaged by human touch (oil, dirt, sweat, etc) they cannot be replaced. I learned to protect it the hard way. I had a personal copy that I lent to an outsider and I never saw it again. He moved and never gave it back.
Superiors, librarians and formation directors do not let them out of our sight, in a manner of speaking.

I don’t open that box everyday to look at it. I just make sure that the box does not leave my cell. Even our novices have never seen it. They’ve asked to see it and I promised them that they will have the privilege of seeing it on the day that they make solemn vows.
Fraternally,
Br. JR, FFV
