Born in Paris, Pascal was taught at the École nationale supérieure des Beaux-Arts by Émile Gilbert and Charles-Auguste Questel.
After brief service in the Franco-Prussian War, he returned to Paris to assist Hector Lefuel with the restoration of the Louvre, and succeeded Questel as the head of his own old atelier.
His other major work includes many monuments and memorial throughout France, the residence and studio of French painter William-Adolphe Bouguereau, 75 rue Notre-Dame-des-Champs, Paris, finished in 1868, and the tomb of Jules Michelet at Père Lachaise Cemetery in 1893.
In 1914, Pascal was awarded both the American AIA Gold Medal in 1914 (the fourth ever awarded) and the Royal Gold Medal of the Royal Institute of British Architects.
Pascal may have had his greatest influence as a teacher, both for French architects and particularly for international students who adapted the lessons of the Beaux-Arts to their home countries.