Buddhism arrived in Afghanistan in the third century BC, when Emperor Ashoka conquered the country and made it a part of the Maurya Empire. Within a century, Buddhism was flourishing in Afghanistan. Buddhist monasteries and large statues of Buddha came up in several parts of Afghanistan and in modern day Pakistan and Transoxania.
When the Chinese pilgrim Hiuen Tsang visited Afghanistan in 610 AD, he found that the Theravada sect of Buddhism was dominant there. In his writings, he mentions that in the Balkh region (Afghanistan’s most prosperous region in that period) there were more than 100 viharas and 3000 monks. He talks about a number of Buddhist centers of learning and holy sites where monks practiced meditation and spirituality. He describes a 35-meter statue of Buddha—he calls this statue Sakyamuni. He describes a statue of Buddha that was 186-meters high—the Bamiyan Buddha. He mentions a third, even larger, statue of the reclining Buddha, located to the east of the monastery in Bamiyan. He notes that the Buddha statues were adorned with gold and fine jewels.
In his 2011 book, History of Buddhism in Afghanistan, Professor C. S. Upasak has described Afghanistan’s Buddhist past and its conversion to Islam after the eleventh century. From his book it becomes clear that most people in the regions of Afghanistan and Pakistan did not convert to Islam directly from Hinduism. First they became Buddhists, which is an offshoot of Hinduism, and a few centuries later, their descendants accepted Islam. The Mongol conquest of the thirteenth century was an important factor in eliminating Buddhism from Afghanistan. The irony is that the Mongols themselves became Buddhist—Mongolia is today a Buddhist majority country.