  We exhibit three double octic Calabi--Yau threefolds over the certain
quadratic fields and prove their modularity. The non-rigid threefold has two
conjugate Hilbert modular forms of weight [4,2] and [2,4] attached while the
two rigid threefolds correspond to a Hilbert modular form of weight [4,4] and
to the twist of the restriction of a classical modular form of weight 4.
