Given the absence of any named satraps (i.e. Achaemenid provincial governors) for Sogdiana in historical records, modern scholarship has concluded that Sogdiana was governed from the satrapy of nearby Bactria. The satraps were often relatives of the ruling Persian kings, especially sons who were not designated as the heir apparent. Sogdiana likely remained under Persian control until roughly 400 BC, during the reign of Artaxerxes II. Rebellious states of the Persian Empire took advantage of the weak Artaxerxes II, and some, such as Egypt, were able to regain their independence. Persia's massive loss of Central Asian territory is widely attributed to the ruler's lack of control. However, unlike Egypt, which was quickly recaptured by the Persian Empire, Sogdiana remained independent until it was conquered by Alexander the Great. When the latter invaded the Persian Empire, Pharasmanes, an already independent king of Khwarezm, allied with the Macedonians and sent troops to Alexander in 329 BC for his war against the Scythians of the Black Sea region (even though this anticipated campaign never materialized).