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A series of cerium-doped compounds with the composition Ba1-xLaxCl2+x and 0 < x < 0.5 have been prepared in ceramic form. We find from the powder X-ray diffraction patterns that the compounds adopt the cubic fluorite structure for 0.05 < x < 0.34. Samples with x ~ 0.2 are translucent. When doped with trivalent cerium, the materials show photoluminescence emission peaks at 350, 372 nm (for the Ba0.66La0.34Cl2.34 composition); the photoluminescence decay can be fitted with a single exponential with decay time 25 ns. The scintillation pulse height analysis shows a photopeak for 137Cs which can be used to compute a light yield of 4000 photons/MeV. The scintillation decay is non-exponential, with a rapid initial decay which can be represented approximately by a decay constant of ~100 ns, but there is a substantial delayed scintillation which extends over several microseconds. [ABSTRACT FROM AUTHOR]