[married21]

Never heard of Milesian legends. What are they?

[RegulatorCountry]

There are a lot of very chatty, ornate recountings but this is very concise and cuts to the chase:

http://www.pantheon.org/articles/m/milesians.html

Iberian soldiers wiped out the natives, known as the Firbolg.

[RegulatorCountry]

... and a more detailed treatment devoid of the genealogical ramblings that tend to go along with the subject:

http://www.hispano-irish.es/en/Common-History-8/1/THE-SPANISH-MILESIAN-INVASION-13