They are primarily concentrated in central Eritrea, in and around the city of Keren and further south toward Asmara, the nation's capital.

The presence of many identical place names in the areas around Lasta and Bogos in central Eritrea further alludes to some historical connection between the two groups.

In the mid to late 19th century during the Egyptian invasion of the Keren highlands (1860-1876) the Bet Tawqe clan accepted Islam, adopting the faith of their new overlords.

The Bet Tarqe clan of the Bilen adopted Catholicism at the hands of French missionaries who offered to protect them from Beni-Amer raids in the area during the second half of the 19th century.

However, the recent migration of other groups into the area resulted in the Bilens taking up other occupations including farming.

In addition, younger Bilen often employ Arabic words and expressions in their everyday speech.