The fall of the Mauryas left the Khyber Pass unguarded, and a wave of foreign invasion folowed. The greeko-bactrian king Demetrius , capitalized on the break up, and he conquered southern Afghanistan and Pakistan around 180 BC, forming the Indo-Greek kingdom.The Indo-Greeks would maintain holdings on the trnas-Indus region, and make forays into central India, for about a century . Under thyem, Budhism flourished, and of their kings Menander became a famous figure of Budhism, he was to establish a new capital of Sagala, the modern city of Sialkot. However, the extent of their domainsand the lengths of their rule are subject to much debate . Numismtic evidence indicates that they retained holdings in the subcontinent right up to the birth of Christ. Although the extent of their successes against indigenous powers such as the Sungas, Satavahans, and Kalings are unclear, what is clear is that Scythian tribes renamed Indo-Scythians, brought about the demise of the Indo-Greeks from around 70 BCE and retained lands in the Trans-Indus , the regio of Mathura, gujarat.