base there, while Alfonso, ruling from Spain, never set foot in Germany and was unable to assert his authority. Both men struggled to gain widespread recognition, enforce their rule, or gain the papal approval necessary for imperial coronation.

The disorder in Germany during the interregnum afforded an opportunity for Count Rudolf to increase his possessions. His wife was a Hohenberg heiress; and on the death of his childless maternal uncle Count Hartmann IV of Kyburg in 1264, Rudolf seized Hartmann's