Pedro José Pidal y Carniado, 1st Marquis of Pidal (25 November 1799 – 28 December 1865) was a Spanish lawyer, writer, politician (alcalde,[2][note 2] deputy and senator) and academician who served important political offices in the reign of Isabella II of Spain, including those of Ministry of Governance,[3] Minister of State,[2] Minister of Justice[4] and speaker of the Congress of Deputies.

On finishing his Law studies, he moved to Madrid in 1822 and started working for a prestigious law firm[2] and collaborated with the short-lived daily El Espectador (1821-3), founded by his fellow Asturian liberal, Evaristo San Miguel.

[5] Before becoming increasingly involved in politics, he briefly (c. 1841) held the Chair of History of Government and Legislation in Spain at the Ateneo de Madrid.

[2] Among the many other reforms carried out by Pidal as Minister of the Interior, the so-called Pidal Plan (1845) —the most important of a series of reforms in Spain's education system that would eventually lead to the so-called Ley Moyano (1857), which would remain in effect until 1970[6]—, implemented the first major overhaul of Spain's education system.

[note 3] The plan also created the first chair in International Law, a post first held, albeit briefly, by Lorenzo Arrazola y García, a former Minister of Justice, future Prime Minister of Spain and President of the Supreme Court.