As a result of the British indifference to local Bengali authority, Siraj ud-Daulah organized his army, captured Calcutta from the British in June 1756, and siege their Fort. After two days of fighting, Governor Roger Drake felt that, it is impossible to withstand the attack and on June 19th, he escaped to Phalta, along with the surviving soldiers. He left behind a number of Anglo-Indian soldiers and civilians, under the civilian command of John Zephaniah Holwell, a senior bureaucrat of the East India Company. Probably, they were left to put up a show of fight and thus provide sufficient cover for Governor Drake’s escape. In the evening of 20th June, Holwell surrendered and finally the fighting ceased. The captives were confined in a cell measuring 14 feet by 8 feet, as a temporary custody by a local commander.

But there was some misunderstanding or some sort of confusion somewhere in the Indian chain of command and the captives were unintentionally left in that overcrowded stuffy prison all through the night. Next morning, when the cell was opened, it was found that out of 146 prisoners, only 23 survived and the remaining 123 died of suffocation and heat. It is interesting to note that, the prison was already called ‘Black Hole ‘before the events of 1756.

This incident was vividly described by J. Z. Holwell in his account on a later date. He had also erected a tablet on the site of the said ‘Black Hole Tragedy’ to commemorate the victims. But somehow, before 1822, it disappeared from the site.

However, some historians have objected to Holwell’s account, claiming that the report produced by Holwell was exaggerated, it is simply not possible to confine nearly 150 persons in a room of that size. Historian Stanley Wolpert opined that, Siraj-ud-Daulah did not order the imprisonment and was not at all informed of it. Historian Ramesh Chandra Mazumder said that, Holwell’s story is completely baseless and cannot be considered as reliable historical information.

Much later, when Lord Curzon became the Viceroy in 1899, he noticed that there was nothing to mark the spot of the Black Hole. At his instance, an obelisk was erected in 1901 at the Southwest corner of the Writers’ Building. However, during the Indian National Movement for independence in 1940, the British had to remove the monument from the spot and rehabilitated it at the compound of St. John’s Church.

It is interesting to note that, a narrow passageway by the northern side of the present GPO building was the site of the guardhouse of the old demolished Fort William. It is said that, the said guardhouse was the cubby hole, which was used as the infamous 1756 Black Hole of Calcutta.

Location of Holwell Monument