The word came to suggest tyranny or ostentatious splendour,[3][4] and its modern usage is a pejorative and refers to any subordinate or local ruler, usually with unfavourable connotations of corruption.
Darius the Great gave the satrapies a definitive organization, increased their number to thirty-six, and fixed their annual tribute (Behistun inscription).
The satrap was in charge of the land that he owned as an administrator, and found himself surrounded by an all-but-royal court; he collected the taxes, controlled the local officials and the subject tribes and cities, and was the supreme judge of the province before whose "chair" (Nehemiah 3:7) every civil and criminal case could be brought.
There were further checks on the power of each satrap: besides his secretarial scribe, his chief financial official (Old Persian ganzabara) and the general in charge of the regular army of his province and of the fortresses were independent of him and periodically reported directly to the shah, in person.
As the provinces were the result of consecutive conquests (the homeland had a special status, exempt from provincial tribute), both primary and sub-satrapies were often defined by former states and/or ethno-religious identity.
Whenever central authority in the empire weakened, the satrap often enjoyed practical independence, especially as it became customary to appoint him also as general-in-chief of the army district, contrary to the original rule.
Exceptionally, the Byzantine Empire also adopted the title "satrap" for the semi-autonomous princes that governed one of its Armenian provinces, the Satrapiae.