Algerian immigration exploded after France's Algerian war ended [causal]
The problem of immigration became an ever hotter issue for any French government to handle, as carnage in Algeria—on top of overpopulation—persuaded increasing numbers of Algerians to seek refuge, and employment, in France. In the winter of 2005–6, outbursts of rage in the overcrowded banlieues, with their substandard housing, gave the lie to the Gaullist notion that, with the end of the war in 1962, France could wash its hands of the "Algerian Problem." Now there are over five million of Algerian extraction living in France.
XREF: Connects to the broader post-colonial migration patterns across Europe and the ongoing France-Algeria tensions that persist today.
Horne, Alistair, A Savage War of Peace- Alge…, loc. 46