Great essay Arathul! Too bad the only reply so far was crap.
With the Northern Dunedain not intermingling with the locals of lesser blood, the question of numbers of men and women comes into play. How many were there at say, the height of Arnor in Elendil's day? Since its given that there was a gradual diminishing in Arnor, from internal dissension and outside forces to the point that the ruling seat was moved from the lake-shore city of Annuminas to the fortress city of Fornost, and the kingdom of Arnor was divided into three in the year 863 of the 3rd Age, with Rhuadur to the east being probably the most mixed population with the hillmen. Cardolan was spread over the rollling southern lands to Tharbad, and was primarily Dunedain though they likely had dealings with the north reach of Dunland. Arthedain remained the strongest state and likely had the most Dunedain population. All three borders met at Amon Sul, or Weathertop, where one of the powerful Palantiri was ensconced.
The north did not have a strong race of men outside the Dunedain which to even really consider intermingling with. The Northmen of Rhovanion were a proud and fierce people in their own right, and probably the the strongest men friendly to the west without being directly from any of the three houses of the Edain. I have to agree that this intermingling in Gondor, despite causing the Kin-Strife, did lead to a strengthening of Gondor with greater numbers of population, and therefore, soldiers to hold the line on Mordor, at the cost of length of lifespan.
Great subject this! I need to finish my tale of the Kin Strife...
Just an informational edit here to inform everyone here that this essay was written by 'Thorin' on Minas Tirith in September 2003. I didn't say anything a few years back when I bumped this as I was hoping there would be more discussion on it. There was, which is a good thing. At the time I let Thorin know that I read and commented on his work he copy/pasted here, assuming that Arathul was his name on this board. It was not as he said he had never registered on Barrow Downs. Thorin was irritated a bit that his post was copy/pasted from another board, but chuffed that there was more discussion on the topic.