The region of Afghanistan has for much of history been part of the Persian empire. From time to time it has been linked with the northern plains of India, as under the Kushan dynasty of the 2nd century AD. Very occasionally, as in the time of Mahmud of Ghazni, it has existed as a kingdom approximating more closely to the modern borders of Aghanistan.
The beginning of modern Aghanistan can be dated to 1747, when the Afghans in Nadir Shah's army return home after his death. Their leader, Ahmad Khan Abdali, enters Kandahar and is elected king of the Afghans in a tribal assembly. He takes the title Durr-i-Durran ('pearl among pearls') and changes the name of his tribe to the Durrani.
Ahmad Shah Durrani, as he is now called, has learnt from Nadir Shah the profession of conquest. He applies his skills with great success over the next twenty-five years. The extent of his empire fluctuates, according to the success of his ceaseless campaigns to protect its boundaries. But for much of his reign Aghanistan extends from the Amu Darya in the north to the Arabian Sea, and from Herat to the Punjab.
Ahmad Shah wins from his people the title Baba (meaning approximately 'father of the nation'). The throne in Afghanistan remains with Ahmad Shah's tribe, though much disputed between his descendants, until they are ousted from Kabul in 1818.