  We present the results of a comprehensive Spitzer survey of 70 radio galaxies
across 1<z<5.2. Using IRAC, IRS and MIPS imaging we determine the rest-frame
AGN contribution to the stellar emission peak at 1.6um. The stellar
luminosities are found to be consistent with that of a giant elliptical with a
stellar mass of 10^11-12Msun. The mean stellar mass remains constant at
\~10^11.5Msun up to z=3 indicating that the upper end of the mass function is
already in place by this redshift. The mid-IR luminosities imply bolometric IR
luminosities that would classify all sources as ULIRGs. The mid-IR to radio
luminosity generally correlate implying a common origin for these emissions.
The ratio is higher than that found for lower redshift, ie z<1, radio galaxies.
