Ogma

Ogma /ˈɒɡmə/ (modern spelling: Oghma) is a god from Irish and Scottish mythology. A member of the Tuatha Dé Danann, he is often considered a deity and may be related to the Gallic god Ogmios. According to the Ogam Tract, he is the inventor of Ogham, the script in which Irish Gaelic was first written.

-https://en.wikipedia.org/wiki/Ogma

Mythology:
He fights in the first battle of Magh Tuiredh when the Tuatha Dé take Ireland from the Fir Bolg. Under the reign of Bres, when the Tuatha Dé are reduced to servitude, Ogma is forced to carry firewood, but nonetheless is the only one of the Tuatha Dé who proves his athletic and martial prowess in contests before the king. When Bres is overthrown and Nuadu restored, Ogma is his champion. His position is threatened by the arrival of Lugh at the court, so Ogma challenges him by lifting a great flagstone, which normally required eighty oxen to move it, and hurling it out of Tara, but Lugh answers the challenge by hurling it back. When Nuadu hands command of the Battle of Mag Tuired to Lugh, Ogma becomes Lugh's champion and promises to repel the Fomorian king, Indech, and his bodyguard, and to defeat a third of the enemy. During the battle he finds Orna, the sword of the Fomorian king Tethra, which recounts the deeds done with it when unsheathed. During the battle Ogma and Indech fall in single combat, although there is some confusion in the texts as in Cath Maige Tuired Ogma, Lugh and the Dagda pursue the Fomorians after the battle to recover the harp of Uaitne, the Dagda's harper.

He often appears as a triad with Lugh and the Dagda (The Dagda is his brother and Lugh is his half-brother), who are sometimes collectively known as the trí dée dána or three gods of skill, although that designation is elsewhere applied to other groups of characters. His father is Elatha and his mother is usually given as Ethliu, sometimes as Étaín. In the Ogam Tract, he is called the son of Elatha and brother of Delbaeth and Bres. Oghma's sons include Delbaeth and Tuireann.

Invention of Ogham:
In the Ogam Tract Ogma is said to be a man skilled in speech and poetry who invented the Ogham as proof of his ingenuity and to create a speech that belongs to learned men apart from rustics. In the same tract Ogma is called the father of the Ogham alphabet, and his knife or hand its mother. The same tract says that sound was the father of Ogham and matter its mother.

References:
-https://www.britannica.com/topic/Ogma

-https://druidnetwork.org/what-is-druidry/deity-and-mythology/many-gods/ogma/

-https://occult-world.com/ogma/

-https://www.godchecker.com/irish-mythology/OGMA/

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