After conquering Conquering the Achaemenid Empire of Persia , the Macedonian king ( and now the great king of the Persian Empire ) , Alexander , launched Military_operation a campaign into the Indian subcontinent in present-day Pakistan , part of which formed Coming_to_be the easternmost territories of the Achaemenid Empire following Motion the Achaemenid conquest of the Indus Valley ( 6th century BC ) .

After conquering Conquering the Achaemenid Empire of Persia , the Macedonian king ( and now the great king of the Persian Empire ) , Alexander , launched Military_operation a campaign into the Indian subcontinent in present-day Pakistan , part of which formed Coming_to_be the easternmost territories of the Achaemenid Empire following Motion the Achaemenid conquest of the Indus Valley ( 6th century BC ) .

After conquering Conquering the Achaemenid Empire of Persia , the Macedonian king ( and now the great king of the Persian Empire ) , Alexander , launched Military_operation a campaign into the Indian subcontinent in present-day Pakistan , part of which formed Coming_to_be the easternmost territories of the Achaemenid Empire following Motion the Achaemenid conquest of the Indus Valley ( 6th century BC ) .

After gaining Getting control Control of the former Achaemenid satrapy of Gandhara , including the city of Taxila , Alexander advanced Cause_to_make_progress into Punjab , where he engaged in battle Hostile_encounter against the regional king Porus , whom Alexander defeated Conquering in the Battle Hostile_encounter of the Hydaspes in 326 BC , but was so impressed Change_sentiment by the demeanor with which the king carried Carry_goods himself that he allowed Preventing_or_letting Porus to continue Motion governing Control his own kingdom as a satrap .

In this phase , Sparta , now receiving support from the Achaemenid Empire , supported Supporting rebellions in Athens 's subject states in the Aegean Sea and Ionia , undermining Athens 's empire , and , eventually , depriving the city of naval supremacy .

In turn , Philip was voted Choosing as `` strategos '' ( general ) for a pan-Hellenic war Hostile_encounter against the Achaemenid Empire , which he had long planned Arranging .