  A Regge model with absorptive corrections is employed in a global analysis of
the world data on positive and negative pion photoproduction for photon
energies from 3 to 8 GeV. In this region resonance contributions are expected
to be negligible so that the available experimental information on differential
cross sections and single polarization observables at -t \leq 2 GeV^2 allows us
to determine the non-resonant part of the reaction amplitude reliably. The
model amplitude is then used to predict observables for photon energies below 3
GeV. Differences between our predictions and data in this energy region are
systematically examined as possible signals for the presence of excited
baryons. We find that the data available for the polarized photon asymmetry
show promising resonance signatures at invariant energies around 2 GeV. With
regard to differential cross sections the analysis of negative pion
photoproduction data, obtained recently at JLab, indicates likewise the
presence of resonance structures around 2 GeV
