Pashtun diaspora comprises all ethnic Pashtuns. There are millions of Pashtuns who are living outside of their traditional homeland of Pashtunistan, a historic region that is today situated over parts of Afghanistan and Pakistan. While the (erstwhile) Pashtunistan is home to the majority of Pashtun people, there are significant local Pashtun diaspora communities scattered across the neighbouring Pakistani provinces of Sindh and Punjab, particularly in their respective provincial capital cities of Karachi and Lahore. Additionally, people with Pashtun ancestry are also found across India; particularly in Rohilkhand, a region in the Indian state of Uttar Pradesh; and in the Indian states of Gujarat and Rajasthan. Outside of South Asia, significant Pashtun diaspora communities are found in the Arab states of the Persian Gulf, the United States, the United Kingdom, Germany, Iran, Australia, Canada, and Russia.

Pashto is an Eastern Iranian language in the Indo-European language family, natively spoken in northwestern Pakistan, southern and eastern Afghanistan, and some isolated pockets of far eastern Iran near the Afghan border. It has official status in Afghanistan and the Pakistani province of Khyber Pakhtunkhwa. It is known in historical Persian literature as Afghani.