Top 10 Free Online Resources for Learning About Irish and Celtic Mythology

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With so many websites, blogs, and books dedicated to Irish and Celtic mythology now available to us thanks to the wonders of the internet, it can be hard to separate the signal from the noise, the wheat from the chaff, the peat from the bog.

Idioms aside, information overload is a real problem when learning about Irish and Celtic mythology, as it is in all disciplines.

In our pursuit of knowledge about ancient Irish and Celtic gods, monsters, and heroes, and their associated myths, legends, and folktales, we want to make sure what we’re learning is accurate, thorough, well-researched, and, ideally, well-written. And that’s exactly why I put together this list of Irish and Celtic mythology resources.

The 10 Best Free Irish Mythology and Celtic Mythology Resources

While not exhaustive by any means, this list of free online resources should, hopefully, appeal to all Irish and Celtic myth aficionados, amateurs and experts alike (and everyone in between).

From introductory posts that offer general overviews of Irish and Celtic mythology (think “Celtic Mythology 101”), to more in-depth, nuanced pieces that explore specific stories and characters in greater detail, chances are there’ll be something here that can help you on your journey.

1) Lewis & Clark College: “Once Upon a Time, Irish Mythology Crash Course”

In this blog post from the Lewis & Clark College website, student Max Usman shares some of the key Irish mythology facts he learned while doing research for his Irish Life & Cultures class. The post gives a great high-level overview of the four cycles of Irish mythology: the Mythological Cycle, the Ulster Cycle, the Fenian Cycle (also known as the Ossianic Cycle), and the King Cycle / Cycle of Kings (also known as the Historical Cycle).

2) Claddagh Design: “A Quick Guide to Irish Mythology”

This quick-hitting guide from the Claddagh Design blog presents a ton of valuable information and insight about Irish mythology and Celtic history. In addition to covering the four cycles (mentioned above), the guide explores the Celtic origins of Irish mythology, explaining how the oral traditions of warrior-farmers from the Alps would eventually leave mainland Europe and reach the Emerald Isle, where they’d be written down and preserved for generations to come.

3) Maricopa Community Colleges: “Irish Myths and Legends”

Ready to dive deeper into the specific battles, adventures, voyages, cattle-raids, romances, pursuits, and tragedies of Irish mythology? This portal from the Maricopa Community Colleges website has got you covered. From “The Landing of the Gael” and “The Battle of Tailltin” (Mythological Cycle), to “The Pursuit of Diarmuid and Grainne” and “The Cattle-Raid of Cooley / Táin Bó Cúalnge” (Ulster Cycle), to “The Fate of the Children of Lir” and “The Wooing of Etain” (Fenian Cycle), links to many of the most well-known Irish myths, legends, and folktales are included here.

4) Mythopedia: “Celtic Mythology”

Easily the most beautifully designed resource on the list, Mythopedia’s page on Celtic mythology is well worth a few minutes (or hours) of perusing. Come for the user-friendly layout and eye-catching graphics, stay for the meticulously researched biographies of Celtic gods, including the horned god Cernunnos (god of beasts and wild places) and the triple goddess The Morrígan (goddess of death and battle).

5) Encyclopedia Britannica: “Celtic Religion: The Celtic Gods”

Yes, I’ve decided to include an entry from the good ole Encyclopedia Britannica on this list, and for good reason: It provides a detailed look at when the Celtic gods of ancient Gaul first appeared in the historical record. Spoiler alert: It was in 52–51 BCE, when Julius Caesar made note of five Celtic gods and their functions. Granted, he used the names of Roman gods rather than their native names. For example, Caesar equated the Roman god Mercury with the Celtic god Lugus, who has cognates in Irish mythology (Lugh) and Welsh mythology (Lleu).

Fun fact: Many place names throughout Europe derive their name from Lugh, including the French cities of Lyon, Laon, and Loudun; the Dutch city of Leiden; the Polish city of Legnica; and a little foggy town in England called London (Lugdunum).

Another fun fact: As the centuries passed and belief in Celtic deities waned, Lugh’s importance was diminished and he became known as “little stooping Lugh” or Lugh-chromain (anglicized as “Leprechaun”).

6) Realm of History: “15 Ancient Celtic Gods and Goddesses You Should Know About”

Here’s another resource that delves into the pre-Christian, Celtic/Gaulish origins of the gods and goddesses that now permeate Irish mythology, and how they were influenced by the Romanization of Western Europe. This thoroughly researched listicle from the Realm of History blog highlights fifteen of the most important ancient Celtic deities, including Belenus (“the effulgent sun god”), Toutatis (“the guardian god of Gauls”), Taranis ( god of thunder), Ogmios/Ogma (god of eloquence), and Epona (“the protector goddess of horses”).

7) ThoughtCo: “Irish Mythology: History and Legacy”

This neatly organized introduction to Irish mythology, written by McKenzie Perkins for the ThoughtCo blog, provides concise answers to broad questions such as “What is Irish Mythology?” and “Who were the most important Irish mythical deities?” The post also highlights the crucial role Irish Christian monks played in shaping, flavoring, and, most importantly, recording Irish myths, which, until the 11th century, had existed primarily as an oral tradition.

8) Illinois Central College Library: “Ancient Civilizations: Celtic Mythology”

Here we have what can best be described as a mini-dictionary of Irish and Celtic mythology. In addition to providing brief biographies of gods and heroes, including Cormac mac Art, Cú Chulainn, and Finn mac Cumhaill, this free resource from the Illinois Central College Library defines key concepts from Irish mythology, including geis (“a magical obligation superseding all other laws and moral imperatives”) and sidhe (“the inhabitants of the fairy Otherworld, who in Irish folklore have frequent congress with mortal man.”)

Fun fact: The banshee from Irish folklore—the female spirit whose haunting shrieks warn of impending death—derives her name from bean sídhe: “woman of the fairies.”

9) University of Pittsburgh: “Folklore, Folktales, and Fairy Tales from Ireland”

This digital library assembled by the University of Pittsburgh’s D. L. Ashliman is the most comprehensive collection of digitized books about Irish myths, legends, folktales, and fairytales on the internet. Period. Examples of the books you can find here (all available via Google Books) include Jeremiah Curtin’s Myths and Folk-Lore of Ireland (1895), Douglas Hyde’s Beside the Fire: A Collection of Irish Gaelic Folk Stories (1890), Joseph Jacobs’s Celtic Fairy Tales (1892), and James Stephens’s Irish Fairy Tales (1920).

10) University of North Carolina School of Information and Library Science: “Irish Folklore and Mythology: A Pathfinder”

Looking for more modern books on Irish mythology? Check out this online pathfinder from the University of North Carolina. While not all of the books and resources listed here are digitized, this pathfinder can help guide you in your research. The “Dictionaries and Encyclopedias” section is especially useful, highlighting Irish and Celtic reference materials such as Daragh Smyth’s Guide to Irish Mythology (1996), Dáithí Ó hÓgáin’s Myth, Legend and Romance: An Encyclopedia of the Irish Folk Tradition, and Peter Berresford Ellis’s Dictionary of Celtic Mythology (1992). LINKS TO THESE BOOKS BELOW!

So there you have it, the ten best free Irish and Celtic mythology resources you can find online. And to reiterate what I wrote in the introduction, this list is by no means comprehensive. If you know of a blog, website, book, or guide to Irish or Celtic mythology that should be on this list, don’t hesitate to send it my way.

Want to learn about the darker side of Irish mythology? Check out…

Samhain in Your Pocket (Celtic Pocket Guides 2)

Perhaps the most important holiday on the ancient Celtic calendar, Samhain marks the end of summer and the beginning of a new pastoral year. It is a liminal time—a time when the forces of light and darkness, warmth and cold, growth and blight, are in conflict. A time when the barrier between the land of the living and the land of the dead is at its thinnest. A time when all manner of spirits and demons are wont to cross over from the Celtic Otherworld. Learn more…

Neon Druid: An Anthology of Urban Celtic Fantasy

“A thrilling romp through pubs, mythology, and alleyways. NEON DRUID is such a fun, pulpy anthology of stories that embody Celtic fantasy and myth,” (Pyles of Books). Cross over into a world where the mischievous gods, goddesses, monsters, and heroes of Celtic mythology live among us, intermingling with unsuspecting mortals and stirring up mayhem in cities and towns on both sides of the Atlantic, from Limerick and Edinburgh to Montreal and Boston. Learn more…

More the listenin’ type?

I recommend the audiobook Celtic Mythology: Tales of Gods, Goddesses, and Heroes by Philip Freeman (narrated by Gerard Doyle). Use my link to get 3 free months of Audible Premium Plus and you can listen to the full 7.5-hour audiobook for free.