The city lies close to Triveni Sangam, "three-river confluence", original name – Prayag, "place of sacrifice or offering" – which lies at the sangam (confluence) of the Ganga, Yamuna and Sarasvati rivers, a propitious place to conduct sacrifices. It plays a central role in Hindu scriptures. Allahabad was originally called Kaushambi (now a separate district) by the Kuru rulers of Hastinapur, who developed it as their capital. Since then, the city has been a political, cultural and administrative centre of the Doab region. In the early 17th century, Allahabad was a provincial capital in the Mughal Empire under the reign of Jahangir.
In 1580, Akbar created the "Subah of Ilahabas" with Allahabad as its capital. In mid-1600, Salim had made an abortive attempt to seize Agra's treasury and came to Allahabad, seizing its treasury and setting himself up as a virtually independent ruler. He was, however, reconciled with Akbar and returned to Allahabad where he stayed before returning to the royal court in 1604.
Located in southern Uttar Pradesh, the city's metropolitan area covers 70.5 km2 (27.22 sq miles). Although the city and its surrounding area are governed by several municipalities, a large portion of Allahabad District is governed by the Allahabad City Council. The city is home to colleges, research institutions and 2 dozen central and state government offices. Allahabad has hosted cultural and sporting events, including Kumbh Mela and the Indira Marathon. Although the city's economy was built on tourism, most of its income now derives from real estate and financial services. The Allahabad district is the second-most revenue providing district in Uttar Pradesh.
Prayag or Prayagraj was the ancient name of this city. The name is a sandhi of the words Pra (Sanskrit: प्र:), meaning 'first' and Yag (Sanskrit: यज्ञ; yajña), meaning 'devotion, worship or offering'. It is believed that Lord Brahma performed the very first yajna in this land. Rig Veda and some Puranas mention this place as Prayag giving it a high religious value in India. The word Prayag also means "Confluence of Rivers". It is here the rivers Ganga, Yamuna and Sarasvati meet. Prayagraj is also called the "Emperor of Five Prayags" (Panch Prayag).
After Mughal invasion, it is said that the Mughal emperor Akbar when visited the region in 1575, was so impressed by the strategic location of the site that he ordered a fort be constructed and renamed it Ilahabas or "Abode of God" by 1584, later changed to Allahabad under Shah Jahan. Speculations regarding its name however, exist. Because of the surrounding people calling it Alhabas, has led to some people holding the view that it was named after Alha from Alha's story.James Forbes' account of the early 1800s claims that it was renamed Allahabad or "abode of God" by Jahangir after he failed to destroy the Akshayabat tree. The name, however, predates him, with Ilahabas and Ilahabad mentioned on coins minted in the city since Akbar's rule, the latter name became predominant after the emperor's death. It has also been thought to not have been named after Allah but ilaha (the gods). Shaligram Shrivastv claimed in Prayag Pradip that the name was deliberately given by Akbar to be construed as both Hindu ("ilaha") and Muslim ("Allah").
Over the years, a number of attempts were made by BJP-led governments of Uttar Pradesh to rename Allahabad to Prayagraj. In 1992, the planned rename was shelved when the chief minister, Kalyan Singh, was forced to resign following the Babri Masjid demolition. 2001 saw another attempt led by the government of Rajnath Singh which remained unfulfilled. The rename finally succeeded in October 2018 when the Yogi Adityanath-led government officially changed the name of the city to Prayagraj.