We (Europe in general) have a demographic problem that will lead to an over aged population because we do not have enough child births. In a couple of years one working person will fund five retired persons. That is of course a no go.
Hence the invitations. We need emigrants and tax payers on a higher level.
Germany put out invitations to India for computer experts and the like.
It did not work out.

The illegal Moroccans in Spain were giving the government an issue cause they were exploited in agricultural plants terribly, fell sick and could not send their kids to school. Hence the free passports, social security, official employment etc. The story is two or three years old. I'll see if I can find something about it.