The GLEAMing of the First Supermassive Black Holes
  We present the results of a new selection technique to identify powerful
($L_{\rm 500\,MHz}>10^{27}\,$WHz$^{-1}$) radio galaxies towards the end of the
Epoch of Reionisation. Our method is based on the selection of bright radio
sources showing radio spectral curvature at the lowest frequency ($\sim
100\,$MHz) combined with the traditional faintness in $K-$band for high
redshift galaxies. This technique is only possible thanks to the Galactic and
Extra-galactic All-sky Murchison wide-field Array (GLEAM) survey which provides
us with 20 flux measurements across the $70-230\,$MHz range. For this pilot
project, we focus on the GAMA 09 field to demonstrate our technique. We present
the results of our follow-up campaign with the Very Large Telescope, Australian
Telescope Compact Array and the Atacama Large Millimetre Array (ALMA) to locate
the host galaxy and to determine its redshift. Of our four candidate high
redshift sources, we find two powerful radio galaxies in the $1<z<3$ range,
confirm one at $z=5.55$ and present a very tentative $z=10.15$ candidate. Their
near-infrared and radio properties show that we are preferentially selecting
some of the most radio luminous objects, hosted by massive galaxies very
similar to powerful radio galaxies at $1<z<5$. Our new selection and follow-up
technique for finding powerful radio galaxies at $z>5.5$ has a high $25-50\%$
success rate.
