Emilio Castelar y Ripoll (September 7, 1832 – May 25, 1899) was a Spanish republican politician, and a president of the First Spanish Republic.

Castelar was born in Cádiz.

He is an eloquent and literary man.

He is appointed dictator of Spain in 1873, but not being equal to the exigency in the affairs of the state, he resigns, and makes way for the return of monarchy, though under protest.

He writes a history of the Republican Movement in Europe, among other works of political interest.