  We show that loitering at high redshifts ($z \gsim 6$) can easily arise in
braneworld models of dark energy which, in addition to being spatially flat,
also accelerate at late times. Loitering is characterized by the fact that the
Hubble parameter dips in value over a narrow redshift range which we shall
refer to as the `loitering epoch'. During loitering, density perturbations are
expected to grow rapidly. In addition, since the expansion of the universe
slows down, its age near loitering dramatically increases. An early epoch of
loitering is expected to boost the formation of high redshift gravitationally
bound systems such as $10^9 M_\odot$ black holes at $z \sim 6$ and lower-mass
black holes and/or Population III stars at $z > 10$, whose existence could be
problematic within the LCDM scenario. Loitering models also help to reduce the
redshift of reionization from its currently (high) value of $z_{\rm reion}
\simeq 17$ in LCDM cosmology, thus alleviating a significant source of tension
between observations of the high-redshift universe and theoretical model
building. Currently a loitering universe accelerates with an effective equation
of state $w < -1$ thus mimicking phantom dark energy. Unlike phantom, however,
the late-time expansion of the universe in our model is singularity free, and a
universe that loitered in the past will approach a LCDM model asymptotically in
the distant future.
