Bishop Cotton Boys' School is an all-boys school for boarders and day scholars in Bengaluru, India, founded in the memory of Bishop George Edward Lynch Cotton, Bishop of Calcutta.

The school is bordered by Residency Road, St Mark's Road, Lavelle Road and Vittal Mallya Road, and is spread over 14 acres (57,000 m) of land in the heart of Bangalore.

School heads in the early days included George Uglow Pope, Herbert Pakenham-Walsh, S. T. Pettigrew, William Elphick, Iowerth Lowell Thomas and A. T. Balraj.

The sister school Bishop Cotton Girls' School is located on the opposite side of St. Mark's Road.

The school's past extends back to the British Raj and the Victorian era with its beginnings in a house on High Grounds over which now stands the great ITC Windsor Hotel. It was started in 1865 by Rev. S T Pettigrew, the then Chaplain of St. Mark's Cathedral who had a vision of starting a school for the education of children of European and Anglo-Indian families. In his own words, he wanted to "establish a day and boarding School for the Children of Christian residents in the station and its vicinity." The school was named in honour of George Cotton, Bishop of Calcutta, under whose stewardship a scheme of education was organized for the Anglican Churches in India. After India gained independence from the British in 1947, the school began to be, and is still governed by the Church of South India.

In the first five years of the school it had three principals. It was only with the arrival of George Uglow Pope, a distinguished Tamil scholar (who translated the famed Tirukkuṛaḷ into English) that the present site was acquired For Rs 47,500. The boys' school and the girls' school functioned on the same campus but under different heads. Under the stewardship of Pope, the school grew from strength to strength. A collegiate section was started and the school obtained recognition from the University of Madras. He gave the School its motto – 'Nec Dextrorsum Nec Sinistrorsum', meaning 'Neither to the right nor to the Left'.

When Pope left India in 1892 to take up the post of Reader at Oxford University, the standard of the school began to decline. By 1906, closure of the school was contemplated.

Henry Whitehead, Bishop of Madras, the chairman of the board of governors, as a last resort, invited the members of the Brotherhood of Saint Peter to save the school from closure. Herbert Pakenham-Walsh, of the Brotherhood of St. Peter, later to become Bishop, revived the school. The school still celebrates St. Peter's day amongst other traditions such as Guy Fawkes' bonfires. In 1911, the girls' school was moved across the road. William Elphick worked for a quarter of century for the growth of the school.

The last living member of the Brotherhood of St Peter in India, Father David, died of old age. He lived and worked in the school as the school chaplain.

Scouting was officially founded in British India in 1909, first starting at the Bishop Cotton Boys' School in Bangalore by Capt T.H Baker and Major Pakenham Walsh.

The General K.S. Thimayya Memorial Trust pays tribute to the School, in memory of General K. S. Thimayya, Cottonian (1918 to 1922). The Trust organises the annual Thimayya Memorial Lecture, and awards the Thimayya Medal to Cottonians who have demonstrated exemplary public service. The Trust also operates a Benevolent Fund that supports former staff members of the School, monetarily.

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