Lord Frederick Charles Cavendish[1] PC (30 November 1836 – 6 May 1882) was an English Liberal politician and protégé of the Prime Minister, William Ewart Gladstone.

Cavendish was appointed Chief Secretary for Ireland in May 1882 but was killed along with Thomas Henry Burke in what came to be known as the Phoenix Park Murders only hours after his arrival in Dublin, a victim of the Irish National Invincibles organisation.

After serving as private secretary to the prime minister, William Ewart Gladstone, from July 1872 to August 1873 he became a junior Lord of the Treasury, and held office until the resignation of the ministry.

His remains were returned to England and buried in the churchyard of St Peter's Church, Edensor, near Chatsworth, on 11 May, where 300 members of the House of Commons and 30,000 other persons followed to the side of the grave.

A statue of Cavendish can be found in the plaza behind the town hall in Barrow-in-Furness in Cumbria (formerly and historically in Lancashire), where his father invested heavily in local industries.