nior coinneadh eigse i rann na feirste do Shean mac maolain agus ba cheart eigse a choinneail do. Could someone please translate coinneadh eigse please. It comes from john ghrainne o duibheannaigh's stair cholaiste bhride.

Accents are important in Irish, as well as upper-case letters.
Níor coinneadh éigse i Rann na Feirste do Sheán Mac Maoláin agus ba cheart éigse a choinneáil dó.

Níor coinneadh X = One did not keep X / X was not kept
(dialect form, Standard Irish: níor coinníodh); see https://www.teanglann.ie/en/fgb/coinnigh
éigse = learning, poetry, wise men, poets; see https://www.teanglann.ie/en/fgb/%c3%a9igse
Éigse = name of a journal

But the meaning is entirely unclear from giving a literal translation of the words.
What does the sentence mean?

Seán Mac Maoláin set up Coláiste Bhríde in Rannafast in the 1920s.

Does it mean:

They didn't maintain the bardic assembly in Rannafast for him, as they should have done?
Or does it mean they should have held a meeting of the bards/poets for him?

Maybe the book it is from has context that would make it clearer?

The next sentence goes. Coinneadh eigse do go leor daoine i Rann na Feirste ach nior coinneadh eigse don fhear a ba chuis leis an cholaiste a bheith i Rann na Feirste o thus go deireadh.
Obviously a form of recognition in the college's history but not sure of the exact meaning, maybe a local thing the people of Rannafast would be know about.

Níl a fhios agam fós cén éigse nár coinneadh don Mhaolánach ...

As it's Ulster Irish I can't be sure of the meaning.
But I'd say the Éigse was never established for him.

In modern times it's a annual assembly in honour of notable poets and sean-nós singers. They have them in all the Gaeltachtaí, as far as I know.