A more thorough and up-to-date discussion of this motif, which the author agrees was quite probably inspired by the ancestors of the Chillingham cattle.
'...the structural position of the poet in each society, is remarkably similar in India and Ireland, and the Irish system remained basically static over the 1000 years from the beginning of our documentation to the collapse of the Gaelic world.' P. 75-6.
A youth spent in the cuire (*Koryos) preceded an adulthood as an aire (*Aryos), meaning a freeman. 
https://t.co/3LG7NDpXBn
What makes this theoretical inclusion of Scotland as a provincial kingdom under the High King of Ireland interesting is that Scotland itself self-identitfied as an Irish colony until the 14th century.
He is believed to have been of Menapian Belgic race, and to have been a ‘citizen of Menapia’, but to have been such he must have belonged to a city of that name, and the city of Menapia (or Manapia) in Ireland (identified with Wexford, Waterford or Ferns) was the only such city. 
R. D. Crewe, 'Brave New Spain: An Irishman’s Independence Plot in Seventeenth-Century Mexico', Past & Present, 207(1), (2010), pp. 53–87. 
Herbert Compton, A particular account of the European military adventures of Hindustan, from 1784 to 1803 (London, 1892). 
'Major McDowell's Offer of Assistance to Britain', Irish Political Review, January 2005, p. 15. 
On a serious note, there is abundant evidence of some kind of connection between the Semitic (or at least Afro-Asiatic) and Insular Celtic peoples. 
Johnston was a Home Ruler of Ulster Protestant background and eventually a senator in the Irish state. 
Molyneux wrote in the interests of fellow Protestant settlers, but his arguments were first formulated by the Old English Confederate Catholic Irish lawyer Patrick Darcy in 1643.
The consequences of the Confederate War were a living legacy until the Land Acts, concluding with the Wyndham Act of 1903, broke the power of the Anglo-Irish landlords in the late 19th century, meaning that Cromwell's impact was continuous until recently. 
There is an idea that the Irish Confederates were Royalists without national consciousness, but Castlehaven, an English Catholic Royalist who fought alongside them, described the Irish rebellion which triggered the Confederate Wars explicitly as a 'Milesian' nationalist uprising.
If we allow ourselves to be mired in this reactive antipathy we will become no better than the German-surnamed teenagers in Idaho who earnestly hate Ireland because it goes with the Boston Brahmin LARP they are performing.
Heinrich Wagner, ‘The Celtic invasions of Ireland and Great Britain: Facts and Theories’ (1987: 19–20), quoted in Hewitt, 'The Question of a Hamito-Semitic substratum in Insular Celtic' in Compass 3/4 (Jul., 2009), pp. 972–995. 