sentences:  The situation worsened after the imprisonment of John II in England following the French defeat at the battle of Poitiers, and in his absence the Provost of Paris, Étienne Marcel, took steps to improve the capital's defences.In 1357, Marcel expanded the city walls and protected the Porte Saint-Antoine with two high stone towers and a ditch.A fortified gateway of this sort was called a "bastille", and was one of two created in Paris, the other being built outside the Porte Saint-Denis.