In 327 BC Macedonian ruler Alexander the Great conquered the Persian Empire provinces of Sogdiana and Bactria, which contained the territories of modern Uzbekistan. A conquest was supposedly of little help to Alexander as popular resistance was fierce, causing Alexander's army to be bogged down in the region that became the northern part of the Macedonian Greco-Bactrian Kingdom. The kingdom was replaced with the Yuezhi dominated Kushan Empire in the 1st century BC. For many centuries the region of Uzbekistan was ruled by the Persian empires, including the Parthian and Sassanid Empires, as well as by other empires, for example, those formed by the Turko-Persian Hephthalite and Turkic Gokturk peoples.