Buddhism was one of the major religions in Afghanistan during pre-Islamic era. The religion was widespread south of the Hindu Kush mountains. Buddhism first arrived in Afghanistan in 305 BC when the Greek Seleucid Empire made an alliance with the Indian Maurya Empire. The resulting Greco-Buddhism flourished under the Greco-Bactrian Kingdom (250 BC-125 BC) and the later Indo-Greek Kingdom (180 BC - 10 AD) in modern northern Pakistan and Afghanistan. Greco-Buddhism reached its height under the Kushan Empire, which used the Greek alphabet to write its Bactrian language.
Numerous Buddhist monks were sent out, including Bodhidharma the founder of Zen Buddhism in China and legendary founder of Shaolin Kung Fu, Lokaksema (c. 178 AD), who travelled to the Chinese capital of Luoyang and was the first translator of Mahayana Buddhist scriptures into Chinese, and Mahadharmaraksita who, according to the Mahavamsa (Chap. XXIX), led 30,000 Buddhist monks from "the Greek city of Alasandra" (Alexandria of the Caucasus, around 150 km north of today's Kabul in Afghanistan), to Sri Lanka for the dedication of the Great Stupa in Anuradhapura. The Greco-Bactrian King Menander I, (Pali) "Milinda," ruled 165 BC - 135 BC, was a renowned patron of Buddhism immortalized in the Buddhist text the Milinda Panha.