Saecula · the method
How Saecula Is Made
Saecula is a Catholic church history timeline you fly over a globe of the real Earth. This page is the method behind it: where every date comes from, how certain each one is, and what we do not claim to know.
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The seven certainty grades
Not every date in salvation history is known the same way. Rather than flatten them, Saecula puts a grade on every moment, and the grade is visible wherever the moment is. These are the seven, in the tool’s own words:
- Scripture Told in Sacred Scripture.
- Documented Recorded by sources from the time, or close to it.
- Approximate It happened; the date or the place is approximate.
- Tradition Handed down from early times but not recorded then: a historical tradition, not Sacred Tradition.
- Pious tradition A devout belief long held in the Church, which the Church has never defined as history.
- Disputed Historians disagree about whether, or how, it happened.
- Apparition A private revelation the Church has approved. It does not add to the deposit of faith (Catechism 67).
A moment’s grade is about the record, not about the faith. “Tradition” here means a historical tradition handed down, not Sacred Tradition. “Disputed” means historians disagree, and we say so instead of picking a side quietly.
Where the facts come from
Saints
The saints come from Wikidata, the public structured-data project, under its CC0 dedication, pulled on 5 October 2026 and filtered automatically. Each saint is placed on the globe where their life ended, or where it began when that is all the record gives. Feast days follow the General Roman Calendar as it is kept in the United States.
Popes
The popes are numbered and dated as in the Holy See’s own list. Where that list shows an overlap rather than a clean succession — 963–965, when it carries John XII, Leo VIII and Benedict V — the Annuario Pontificio notes that which of these claims was the legitimate one cannot be settled, so Saecula shows them together rather than choosing for the reader.
They are also written out in order, as plain text, on their own page: all 267 popes in order, from St. Peter to Leo XIV.
The twenty-one ecumenical councils
All twenty-one councils the Church recognizes as ecumenical are on the timeline, each with its place, its years, what it settled and the sources behind it. They are also written out in order, as plain text, on the timeline page: the twenty-one ecumenical councils, in order.
Feasts and the liturgical day
The day’s feast comes from this site’s own liturgical engine, the same one that drives the Today view in the 1765 Sanctum app, checked against the published calendars of the United States Conference of Catholic Bishops.
Scripture
Scripture is quoted in the Douay-Rheims; the opening line of Genesis is also given in the Latin of the Vulgate. Other Latin is named where it appears (Tertullian; the Creed). All of it is public domain. Saecula does not reproduce the official English of the Mass or of the other rites, which is copyrighted by the International Commission on English in the Liturgy: liturgical formulas are given in Latin with our own explanation, or in verified public-domain English.
Maps and journeys
Coastlines are Natural Earth, which is public domain. Journeys and places are drawn approximately; a line on the globe shows a route, not a surveyed path.
What we do not date
Some things are held firmly as true and are not datable, and Saecula refuses to invent a year for them.
- Creation, the Fall and the Flood carry no dates. They are placed before the dated record begins. Eden is drawn, not located. The Catechism says Genesis 3 “uses figurative language, but affirms a primeval event” (390), and that these chapters may have had diverse literary sources (289).
- Abraham is given a range, not a year. His call is “often placed c. 2000–1800 BC”, and the page says plainly that the dating is not certain.
- The Last Things are undated. The final chapter closes the flight with no year at all, because the day and the hour are not ours to know (Catechism 673).
- The seven ages are a frame, not a chronology. They follow St. Augustine (City of God XXII.30), whose seventh age is the sabbath rest, not a span of years.
How the entries are written and checked
Saecula is built under strict guardrails for fidelity to Catholic doctrine, tradition and theology. Entries are drafted with AI assistance, checked against their sources, and reviewed by a human editor. Mistakes can still happen. If you find one, please tell us.
The human editor is the founder of 1765 Sanctum Co. No priest or theologian reviews the entries, and Saecula never claims one does.
Sources, in full
Saints: Wikidata (CC0), pulled 5 October 2026 and filtered automatically; feast days from the General Roman Calendar as kept in the United States. Popes: numbered and dated as in the Holy See’s list. Each saint is placed where they died, or where they were born when that is all the record gives. Coastlines: Natural Earth (public domain). Journeys and places are drawn approximately. The seven ages follow St. Augustine (City of God XXII.30), whose seventh age is the sabbath rest, not a span of years. Scripture: Douay-Rheims and the Vulgate (public domain).
Image and music credits
Art (public domain unless noted): Rembrandt, Jacob Blessing the Sons of Joseph (1656, Kassel); Gerard van Honthorst, Adoration of the Shepherds (1622, Wallraf-Richartz-Museum, Cologne); Diego Velázquez, Christ Crucified (c. 1632, Prado); Jusepe de Ribera, Penitent Saint Peter (c. 1630, Art Institute of Chicago); Josep Serra i Porsón, Ignatius of Loyola wounded at the battle of Pamplona, 1521 (lithograph, Historia de España ilustrada, Barcelona, 1875); Caravaggio, Madonna of the Rosary (c. 1607, Kunsthistorisches Museum, Vienna); Andrea Pozzo’s ceiling of Sant’Ignazio, photo by Camilleparis (CC0). Music: Palestrina, Sanctus, Osanna and Benedictus from Missa Sicut lilium inter spinas, sung by The Tudor Consort (from the Free Music Archive, via Wikimedia Commons), re-encoded, used under CC BY 3.0 Unported (creativecommons.org/licenses/by/3.0).
Found an error?
Write to [email protected] and name the moment. Corrections are made at the source, so the fix reaches the globe, the timeline and this page together.
Excerpts from the English translation of the Catechism of the Catholic Church for use in the United States of America Copyright © 1994, United States Catholic Conference, Inc. -- Libreria Editrice Vaticana. Used with Permission. English translation of the Catechism of the Catholic Church: Modifications from the Editio Typica copyright © 1997, United States Conference of Catholic Bishops—Libreria Editrice Vaticana.