Explanation:

• Bactrians & Parthians (Iranians) became independent from Syrian (Greek) rule around 300 BC Around 200 BC, B.C.Demetrius, the Greek ruler of Bactria invaded Afganistan & Punjab & occupied them.
• From Taxila he sent his 2 commanders, Appolodotus & Menander for further conquest Appolodotus conquered Sindh & marched upto Ujjain Menander extended his rule upto Mathura & from there attempted to capture Patliputra, but was stopped by Vasumitra (Grandson of Pusyamitra Sunga) Menander, also called Milinda, formed his capital at Sakala (Sialcot) & took great interest in Buddhism.
• His dialogues with Buddhist monk Nagsena were compiled in Pali work “Milindpanho” or questions of Milinda.
• Milinda, finally embraced Buddhism under Buddhist monk Nagarjuna Greeks were followed by scythians (Shakas) who controlled much larger area of India then Greek did.
• There were 5 branches of Shakas in 5 different directions in India & Afghanistan.