Abstract
New measurements of the extragalactic diffuse γ-ray background show that its spectrum above 30 MeV can be well described by a power law with photon index α=2.1. In the 2–10 MeV range a preliminary analysis of COMPTEL data indicates a lower intensity than previously found, with no evidence for an MeV bump. Most of the models of a truly diffuse background seem to be in conflict with the observed spectrum. Though AGN are the most likely input from discrete sources, two independent attempts to model the high energy background as the superposition of unresolved AGN indicate that AGN underproduce the observed intensity. Therefore the origin of the extragalactic γ-ray background is still unknown.
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