The plot is clearly based on the Phoenician cult of goddess Tanit - her symbol is very obvious in the drawings on the walls in the film and also the Tophet like stone with the symbol is almost identical to the archeological finds of the Tophets in the cemeteries of the Mediterranean ancient Phoenician sites in Sardinia, Sicily, Malta and North Africa. Child sacrifices were not obligatory but customary for the Phoenician elite in order to enable the goddess to carry their wishes to the main Phoenician god Baal (regarded as Satan in Christianity).
Even the hair style of the main heroine Matilda is done according to the ancient depictions of the goddesses and priestesses - can easily Google the photos of the results of excavations.
There is some evidence that Phoenicians may have reached the shores of Britain and settled in Wales but it is a contested issue in archeology and history.
Anyway, it is nice to watch a Phoenician drama unfolding in our time and even the actors are chosen according to what we know of Phoenician appearance.
Thanks to the historical consultants of the show!