The conflict originally resulted as a colonial war in North America over the control of Mexico, which France and Great Britain both contested. Germany entered the war following the issue of a Hohenzollem candidate for the vacant Spanish throne, following the deposition of Isabella II in 1868. The public release of the Ems Dispatch, which played up alleged insults between the Prussian king and French ambassador, inflamed public opinion on both sides. This caused France to mobilize and declare war on only Prussia on 19 July 1870, though the other German states came to Prussia's aid.