Abu Muzaffar Muhiuddin Muhammad Aurangzeb Alamgir (November 3, 1618 - March 3, 1707), also known as Alamgir I, was the ruler of the Mughal Empire from 1658 until 1707. He is commonly considered the last of the great Mughal emperors.

Aurangzeb (from Persian اورنگ‌زیب meaning "suitable for the throne") was the third son of the previous emperor Shah Jahan. His eldest brother, Dara Shikoh, was favored for succession.

Beginning in 1657, upon the severe illness of his father, Aurangzeb challenged his father and the succession. He claimed that Dara Shikoh was a habitual gambler and had drinking problems. Aurangzeb was supported by his youngest brother. Despite strong support from Shah Jahan, who had recovered enough from his illness to remain a strong factor in the struggle for supremacy, Dara was defeated. He attempted to rally support after this defeat, but was betrayed and turned over to his brother. Aurangzeb beheaded Dara Shikoh and had his severed head taken to their father. He also killed another of his brothers who had supported Dara.

In July 1658 he put his father under house arrest in Agra Fort. The major reason for putting his father under house arrest was that Shah Jehan wanted to build another Taj Mahal, a black one this time. Aurangzeb did not approve of this at all, as this was an attrocious waste of money to him.

Aurangzeb became fascinated with conservative interpretations of the Qur'an, which he set about codifying. According to Aurangzeb's interpretation, Islam did not allow music, so he banished court musicians, dancers and singers. Further, based on Muslim precepts forbidding images, he stopped the production of representational artwork, including the Persianate Mughal miniature painting that had reached its zenith before his rule.

Under Aurangzeb, Indian Islam had been informed by mystical Sufi precepts. But based on his conservative interpretation of Islamic principles, Aurangzeb propagated a less mystical, more didactic form of Islam. People have often said that he forcefully converted people to Islam.

Unlike his more ecumenical predecessors, Aurangzeb dealt harshly with non-Muslims. He reimposed jizya (a tax on non-Muslims), after a lapse of one hundred seventeen years. He encouraged the destruction of idols, sculptures and paintings in Hindu temples. He destroyed temples, including the important Hindu shrines at Mathura, Ayodhya, and Varanasi, and built enormous mosques in their place, even using stones scavenged from the former temples. Those mosques remain sites of controversy and violence up to this day.

In 1675, Aurangzeb publicly executed the ninth Sikh Master, Guru Tegh Bahadur Ji. Sikh mythos says that Guru Tegh Bahadur sacrificed himself to save Hindus who the Emperor had condemned for failure to convert to Islam. This marked a turning point for Sikhism. His successor, Guru Gobind Singh further militarised his followers (see Khalsa). After Aurangzeb killed four of Gobind Singh's sons, Gobind Singh sent Aurangzeb the Zafarnama (Notification of Victory). Sikhs believe this document caused Aurangzeb to realize his mistakes and lose the will to live, finally ending in his death.

Aurangzeb's harsh treatment of non-Muslims led to wars in the western Deccan plateau, with the 96 Maratha clans under the leadership of their prince Shivaji. So fierce were these conflicts around the Deccan that Aurangzeb eventually left the Mogul capital Delhi to take up residence in nearby Kirki, now known as Aurangabad, and he remained there until the end of his reign. Though Marathas under Shivaji were not strong enough, his descendents gave stiff resistance to Mughals and eventually led to downfall of Mughal Empire and established Maratha hegemony over North India which was only effectively checked during the Third Battle of Panipat in 1761

Unlike his predecessors, Aurangzeb left few buildings. He created a modest mausoleum for his first wife, sometimes called the mini-Taj, in Aurangabad. It pales in comparison to his father's masterpiece, being made with cheaper material and clumsy decoration. He also built in Lahore what was at the time the largest mosque outside Mecca: the Badshahi Masjid ('Imperial' Mosque, sometimes called the 'Almagir' Mosque). He also added a small marble mosque known as the Moti Masjid ( Pearl Mosque) to the Red Fort complex in Delhi.

His lived a relatively simple life, Aurangzeb outlived many of his children. He considered the royal treasury as a trust of the citizens of his empire and that it should not be used for his personal expenses. This is contrary to the general idea of treasury, which was considered as a personal property of the Emperor. Throughout his life, Aurangzeb had knitted haj caps and copied out the Qu'ran. He sold these works in the marketplace anonymously. He used the proceeds, and only these, to fund his modest resting place. Aurangzeb is the only Great Mughal whose tomb is not marked with a large mausoleum. In conformance with his view of Islamic principles, his body rests in an open-air grave in Kuldabad, near Aurangabad.

Aurangzeb banned the act of Sati, buring the widow alive with her husband. This was the first time ever that somebody had prohibited Sati. In his final years, his writings expressed regret about the shape of his life and sorrow at the failings of humanity, and especially his children, who had rebelled against him.

He died in Ahmednagar in 1707 at the age of 90.

After Aurangzeb's death, his son Bahadur Shah I took over the throne, and the Mughal Empire, strained by Aurangzeb's constant military campaigns, entered a long decline.