Moulouya River
After the death in 40 AD of Ptolemy of Mauretania, the last Ptolemaic ruler of the Kingdom of Mauretania, in about 44 AD Roman Emperor Claudius annexed the kingdom to the Roman Empire and partitioned it into two Roman provinces: Mauretania Tingitana; and Mauretania Caesariensis. The Mulucha (Moulouya River), located around 60 km west of modern Oran, Algeria, became the border separating them.