Diana (Dayna) in Roman mythology was the goddess of the hunt, associated with wild animals and the woodlands. She would later become a moon goddess supplanting Luna. Her symbol was the crescent. Worshipped mainly by women as the giver of fertility and birth, her name is thought originally to have been of Greek origin and derived from the word "divana"(the shining one)".
The Irish goddess Anu known also as Danu, was the mother figure who accompanied the Dagda (genitive Danan). Irish Literature names these last and most favoured generation of deities as "the people of Danu or Dana (Tautha De Danan), also referred to as the shining ones.
Dana (Dayna) was the pagan goddess who bestowed her name on these legendary early inhabitants of Ireland. These Tauth De Dannan connect in Irish mythology and ancient historical pedigrees topographically located with groups such as the Fir Domnann of Leinster, the Laigin dynasty, the Cianacht (sons of Cian) the Fir Gallion (Gaileanga) and Luighne.
Their mythological origins link back to history and cultural alignments associated 1st with the Ui Baircche, Eoghanacta and Eoghan Mor (Mugh Naudat), a king of Munster, whose nickname Nuada is found later in the mythology of the Tauth De Danan, represented by the symbolic sword of Nauda and crescents of Danu, adopted as part of the heraldic crests of Moylan, Mullen and McMullen of Leinster and Connacht
A unique aspect to Irish heraldry is that Gaelic symbols are also literary, example the arm of Nauda, King of the De Danann Gods, remembered with this symbol of a hand holding a sword. Nauda lost his arm in battle. Since an Irish King could not be disfigured and still rule, lore has him abdicate his throne. His divine silversmith Dian Cech, fashions a silver arm for him, attaching it with magic to his body, allowing him to reclaim the throne. The illustrated hand holding a sword is recalling this mythological event in Irish literature.
Nauda in Gaelic means "cloud maker". Mythology is a strange and fascinating mixture of legend, truth and fiction, but many elements of these tales link profoundly to topographical areas in Westmeath (Uisneach) and Brega (Tara) where our ancestors once dwelled as tribes of the Luighne and Gaileanga, For some appreciation of that, go to the section titled the Stone of Lugh.
Movement of these Gaileanga and Luighne (Lugh) septs bearing surname variants of Maelan, Maolain and Mac Maolain can be tracked in the Irish Annals as well as townland and place names associated with them.
These verbal identifiers suggested by most experts to have emerged 5th-10th century, surface in the dynastic territories of the Ui Baircche, Leinster Laigin, Connacta Ui Briuin and Ui Neill (Southern): Bailie Maolain alias McMullen in Co. Laois and Abbyleix, Bailie Maolain Kilclonfert Co. Offaly; Doire Maolain Ballinasloe, Baillie Maolain Loughrea, Ros Maolain Ballynakill Galway, Cluain Mhic Mhaolain Kilnamanagh in Co. Roscommon, Baillie Moelan Ardee Louth and Maelan Co. Cavan (part of Briefne Connacht pre plantation).
All these locales were inhabited at some point by septs bearing a surname variant of Maelan, Maolain, Mailin, Mhic, Mac and Mic Maoláin (Mullen, Moylan, McMullen, McMullan, McMullin), displaying the crescent of Danu on their banners, reflecting the adoption of these cultural dieties.
Other Irish septs displaying this crescent of Danu as part of their heraldic symbols are: Breen, O'Beirne, Cullen, Dolan, Haughey (=Eochaid), Kavanagh, Maher, Malen, Mannion, Mullally, Mullaney, Mulduin, Quinn, Rynne and the MacLoughlin Ui Neill kings of Tara.
Based on heraldry as an additional method of historic research, this may be suggestive of very ancient ethnic and military alliances. One example could be septs Mannion and Malen (sometimes recorded as Maeleainn, Millionor O'Mellon Delvin) plus O 'Mullen, who were located adjacent each other based on historical references in Westmeath, Meath and also NE Galway.
All display very similar crests. O'Maolain (Mullen) Connacht and Mac Maolain McMullen) Leinster on all official heraldic sites are found illustrated with this crescent and the addition of the hand with a sword or dagger (Nauda) incorporated.
Heraldic description: Ar. dexter hand couped at the wrist in fess gu. holding a sword/dagger in pale proper between three crescents gu (gules
Gules (Red) = Warrior, Martyr, Military Strength
Crescent Moon= Enlightened, Honored by his Sovereign
MacLysaght who was the first Chief Herald under the Government of Ireland (post 1921) designated many Gaelic families who had arms pre dating the creation of the office of the King of Arms as having "Sept Arms" that could be used, undifferentiated, by anyone who genuinely descended from that Sept. For Clan McMullen members that crest is:
Mac Maoláin (http://www.allfamilycrests.com/)
To the north in the province of Ulster, the sept O'Mullan of Coleraine and Derry (said to be descendants of Ui Neill Clan Drugain), are shown to have a completely different crest based on summaries posted by their historical overlords O'Cathain. The O'Mellens (Meallain and Mic Meallain (Clan Fergusa) of Tyrone, keepers of St Patricks Bell, also display a different crest as illustrated below.
The founding Royal family of the Fir Domnnan dynasty Caomanaich (Kavanagh) have this ancient crescent symbol in their banner.
Early Irish pedigrees position Ui Maelan (Moylan, Mullen) as part of the tribal clusters (Ui Bairrch Magh Ailbe) associated with Eochaid Guineach (Haughey)