Qadian (Punjabi pronunciation: [käːd̪ijä̃ː]; Hindustani pronunciation: [qɑːd̪ijɑ̃ːn]) is a town and a municipal council in Gurdaspur district, north-east of Amritsar, situated 18 kilometres (11 mi) north-east of Batala city in the state of Punjab, India. Qadian is the birthplace of Mirza Ghulam Ahmad, the founder of the Ahmadiyya movement within Islam. It remained the headquarters of the movement until the Partition of India in 1947.

Qadian was established in 1530 by Mirza Hadi Baig, a religious scholar dedicated to Islam and the first Qazi in the area. Mirza Hadi Baig was from a royal household of Mirza of the Mughal Empire. He migrated from Samarkand and settled in Punjab where he was granted a vast tract of land comprising 80 villages by the emperor Babur. Because of his religious beliefs, he named the center of the 80 villages Islam Pur Qazi and governed from there. Over time, the name of the town changed to Qazi Maji, then Qadi, and eventually it became known as 'Qadian'. The term Qadiani is used as a slur to refer to Ahmadi Muslims, primarily in Pakistan.

Qadian and the surrounding areas later fell to the Ramgarhia Sikhs under the leadership of Jassa Singh Ramgarhia who offered the ruling Qazis, two villages which they refused. In 1834, during the rule of Maharaja Ranjit Singh, the region consisting of Qadian and five adjoining villages was given to Mirza Ghulam Murtaza, father of Ghulam Ahmad in return for military support in Kashmir, Mahadi, the Kulu valley, Peshawar and Hazara.

A remote and unknown town, Qadian emerged as a centre of religious learning in 1889, when Mirza Ghulam Ahmad established the Ahmadiyya Muslim Community. It was historically a Muslim-majority town, a Muslim enclave within the wider Gurdaspur District in British Punjab.

In 1891 it became the venue for the community's annual gatherings. Qadian remained the administrative headquarters and capital of the Ahmadiyya Caliphate until the partition of India in 1947, when much of the Community migrated to Pakistan.

Prior to the Partition of India, Qadian being the central headquarters of the Ahmadiyya Muslim Community, had around 14,000 Ahmadis spread across approximately 19 different neighborhoods and villages. Following the partition, Mirza Bashir-ud-Din Mahmud Ahmad, the second Khalifa of the Community, carefully oversaw the safe migration of Ahmadis from Qadian to the newly founded state, instructing 313 men, including two of his own sons, to stay in Qadian and guard the sites holy to Ahmadis, conferring upon them the title darveshān-i qādiyān (the dervishes of Qadian) and eventually moving the headquarters to Rabwah, Pakistan.

Qadian experienced extreme violence and bloodshed during and after the partition of India, and many of its neighbouring areas and villages became devoid of Muslims, who were either lynched or displaced by militant Sikhs and Hindus backed by the Indian Army at that time. Despite many Muslims deciding to remain in India, in Qadian or its neighboring areas, they were, at a low, persecuted, or forthrightly killed. A curfew on Qadian was intermittent for several months after the partition. Many religious places were either forcibly occupied and converted, defaced, ransacked and or vandalised.

At the height of violence during the partition, Qadian had become a makeshift refugee camp for over 50,000 displaced Muslims.