Henry David Leslie (18 June 1822 – 5 February 1896) was an English composer and conductor. Leslie was a leader in supporting amateur choral musicians in Britain, founding prize-winning amateur choral societies. He was also a supporter of musical higher education, helping to found national music schools.
Leslie was born in London. His parents were John Leslie, a tailor and enthusiastic amateur viola player, and Mary Taylor Leslie. He had eight brothers and sisters. He attended the Palace School in Enfield and worked with his father. As a teenager, he studied the cello with Charles Lucas and later played that instrument in concerts at the Sacred Harmonic Society for several years.
Leslie began to compose music, and in 1840 he published his Te Deum and Jubilate in D. He became honorary secretary of the newly founded Amateur Musical Society in 1847. His symphony in F was performed in 1848 by the Amateur Musical Society under Michael Balfe. The next year, at the Norwich music festival of 1849, his much-admired anthem "Let God Arise" was premiered. He conducted the Amateur Musical Society from 1853 until it dissolved in 1861.
Leslie's dramatic overture, The Templar (1852), was followed by and his well-regarded oratorios Immanuel (1854) and Judith (1858), and some chamber music. In 1855, he founded a madrigal society which grew to 200 voices and became known as Henry Leslie's Choir. He was its conductor until 1880. The choir introduced many important choral works to English audiences, including J. S. Bach's 18-part motets. According to The Times, this choir "held the palm among London societies for finished singing of unaccompanied music, both ancient and modern".
In 1857, Leslie married Mary Betsy, one of his pupils, the daughter of physician William Henry Perry. The couple moved to Mary's family home, now known as Bryn Tanat Hall, at Llansanffraid, near Oswestry on the Welsh border. They produced four sons and one daughter. Their son William became a master of the Musicians' Company, and Charles became a cricketer for Middlesex and England.