AbstractFamilies of Portuguese origin settled in the Saint-Esprit&#8217;s seigniory facing Bayonne, a city where they could not be admitted. There they were allowed to live a Jewish life and they worked patiently and succeeded in settling out of reach of water the bank of the river Adour that up till then got under water twice a day. Thus an urban space was created which grew during the XVIIth century. In Bayonne people dealt with their various items of business during the day&#160;; their family and religious life was spent in Saint-Esprit. Their bearings in the realm of France more vulnerable than those of their Christian neighbors, made them still more aware of the necessity to seek the protection of the king and of the fact that the French space was all dedicated to the king and his court. Moreover they belonged to the western Sephardic diaspora thanks to very strong family links, established through marriages which were made, one generation after another, between their families and those of Portuguese Jews from London, Amsterdam and Hamburg.