Leabhar (Mór) Leacain “The (Great) Book of Lecan” was written 1397-1418 in Middle Irish by the Gaelic poet-historian Giolla Íosa Mór Mac Firbhisigh for Ádhamh Ó Cuirnín. This section relates to the inauguration of the leader of the Uí Fiachrach, given the title “Ó Dubhda”; Ó Caomháin is Ó Dubhda’s main vassal.
The privilege of taking the first drink [at the inaugural banquet] was given to Ó Caomháin by Ó Dubhda, and Ó Caomháin was not to drink until he presented the drink to Mac Firbhisigh, the poet; Ó Dubhda’s arms and battle steed were given to Ó Caomháin after the proclamation and it is not proper to ever proclaim the new ruler “the Ó Dubhda” until Ó Caomháin and Mac Firbhisigh have first done so and Mac Firbhisigh has brandished the wand (of sovereignty) over Ó Dubhda; every church official, bishop and territorial chief are to all proclaim the name after Ó Caomháin and Mac Firbhisigh. […] it was Amhalgaidh, the son of Fiachra Ealgach, that built that cairn for himself, in order that he and all those who should obtain the lordship after him, might be proclaimed lord on it. And it is in this cairn that Amhalgaidh himself is buried, and it is after him that it is named. May every king of the Fiachra who is not nominated in this way have a short life, and his descendant lack success, and may he never see God’s heavenly kingdom.