First, Alexander had to impose himself against usurpers trying to seize his throne: his cousin Amyntas and the family princes who controlled a region called Lincestida. Alexander's actions were effective, and Amyntas and the princes of Lincestida were executed at the behest of the Macedonian king.
In addition, peoples under Macedonian rule - notably the Illyrians - took advantage of the instability of power and attacked the Macedonians. Alexander quickly circumvented these rebellions. Finally, a rumor of his death in battle against the Illyrians caused the city of Thebes to rebel against the Macedonians. Alexander regained it, crushed the rebellion, and offered the sack of the city to his soldiers as a punishment to the Thebans.
After consolidating his power in Macedonia and Greece, Alexander formed a large army of Greeks, Macedonians, and other conquered peoples, such as tribals and peonies, and began the Persian-dominated Asian conquest campaign since 334 BC. Antipater as trusted ruler.
Alexander arrived in Asia Minor at the beginning of 334 BC, accompanied by approximately 50,000 soda. He began the conquest of the region with a great battle fought in April of the same year: the Battle of Grânico. The record shows that in this battle large numbers of Persian cavalry soldiers were killed by Alexander's armies and the victory was the Macedonians.
This victory allowed Alexander to extend his control over countless cities in the region once Persian power had been weakened. Thus, in a short time, all Phrygia and Lydia were conquered by Alexander. A final focus of Persian resistance focused on Halicarnassus and was also defeated. With the conquests, Alexander transformed these cities of Greek origin into democratic poles.
The causes of Alexander's death are not known for certain, but it is currently speculated that Alexander may have died of typhoid or malaria (the hypothesis of poisoning is not widely accepted by historians). Alexander's death led to a succession crisis, since there was no established heir (his wife Roxana was pregnant). Then began a power struggle between Alexander's generals, which led to the fragmentation of the Macedonian Empire.