1778 deaths

François-Marie Arouet (21 November 1694 – 30 May 1778), known by his nom de plume Voltaire (, ), was a French Enlightenment writer, historian, and philosopher famous for his wit, his criticism of Christianity—especially the Roman Catholic Church—as well as his advocacy of freedom of speech, freedom of religion, and separation of church and state.

Anna Maria Walburga Mozart (née Pertl; December 25, 1720 – July 3, 1778) was the mother of Wolfgang Amadeus Mozart (1756–1791) and Maria Anna Mozart (1751–1829).

Jean-Jacques Rousseau (, , 28 June 1712 – 2 July 1778) was a Genevan philosopher, writer, and composer. His political philosophy influenced the progress of the Enlightenment throughout Europe, as well as aspects of the French Revolution and the development of modern political, economic and educational thought.

Anne Steele (pen name, Theodosia; 1717 – 11 November 1778) was an English Baptist hymnwriter and essayist. For a full century after her death, she filled a larger place in United States and British hymnals than any other woman.

Ignatius Gottfried Kaim was an Austrian chemist. In his dissertation De metallis dubiis published in 1770 Kaim describes the reduction of manganese oxide with carbon and the formation of a brittle metal. This is the first description of manganese metal several years before the better known synthesis of Johan Gottlieb Gahn in 1774.

Thomas-François Dalibard (born in Crannes-en-Champagne, France in 1709, died in 1778) was a French physicist who performed the first lightning rod experiment. He was married to the novelist and playwright Françoise-Thérèse Aumerle de Saint-Phalier.

Michel-Ange Du Quesne de Menneville, Marquis Du Quesne (c. 1700 – 17 September 1778) was a French Governor General of New France. He was born in Toulon, France.

Francesca Cuzzoni (2 April 1696 – 19 June 1778) was an Italian operatic soprano of the Baroque era.

Philip Livingston (January 15, 1716 – June 12, 1778) was an American merchant, politician and slave trader from New York City. He represented New York at the October 1774 First Continental Congress, where he favored imposing economic sanctions upon Great Britain as a way of pressuring the British Parliament to repeal the Intolerable Acts. Livingston was also a delegate to the Second Continental Congress from 1775 to 1778, and signed the Declaration of Independence, thus becoming one of the Founding Fathers of the United States.

Sir George Hay (25 January 1715 – 6 October 1778) was a British judge and politician who sat in the House of Commons between 1754 and 1778. He committed suicide.