Thanks for posting this. Quoting the reporter in the article:
“The demographics of Portugal are so striking, with nine million people in the western half and just one million in the east. There are areas in eastern Portugal with a lower population density than the Highlands of Scotland.”
This is an amazing statistic in and of itself because Portugal is never really thought of in terms of east and west, at least not in my experience. Culturally, if there's a divide it's more north-south, while administratively, regions are not split in a way that differentiates east from west. This map shows how four of the five greater regions of Portugal traverse the territory from the (west) coast to the (east) Spanish border. There are smaller regions within these larger ones but at least in the case of the Beiras and the Alentejo, they are still divided more on a north-south ('upper' and 'lower') axis than an east-west one.
More importantly, that statistic helps contextualise things I thought about while walking in the east of Portugal this year on the Caminho Nascente. What we came across was a far more rural, far more depopulated part of Portugal than on the CP from Lisbon last year. In general, the camino can be referred to as a village-to-village walk, but not all 'villages' are created equal and we found a significant difference in the size of the villages on each camino (i.e. that villages on the Nascente might have a population of as few as two people, no services at all, and a greater distance to the next village). We put all of this down to spending a lot of time walking in the Alentejo, which is depopulated in general, but now I see that this dramatic east-west population divide helps explain this a lot more.