An electric field loading stage was designed for use in a laboratory diffractometer that enables in situ investigations of the temperature dependence in the field response mechanisms of ferroelectric materials. The stage was demonstrated by measuring PbZr1-xTixO3 (PZT) based materialsa commercially available PZT and a 1% Nb-doped PbZr0.56Ti0.44O3 (PZT 56/44)over a temperature range of 25 degrees C to 250 degrees C. The degree of non-180 degrees domain alignment ((002)) of the PZT as a function of temperature was quantified. (002) of the commercially available PZT increases exponentially with temperature, and was analyzed as a thermally activated process as described by the Arrhenius law. The activation energy for thermally activated domain wall depinning process in PZT was found to be 0.47 eV. Additionally, a field-induced rhombohedral to tetragonal phase transition was observed 5 degrees C below the rhombohedral-tetragonal transition in PZT 56/44 ceramic. The field-induced tetragonal phase fraction was increased 41.8% after electrical cycling. A large amount of domain switching ((002)=0.45 at 1.75 kV/mm) was observed in the induced tetragonal phase.