Alarmed by these events, the other European powers convened in October 1822 at the Congress of Verona and authorized France to intervene in the conflict and restore the rule of Ferdinand, with only Britain abstaining from that decision.

On 17 April 1823, French forces led by Louis-Antoine, Duke of Angoulême, son of the future Charles X, crossed the Pyrenees into Spain.

The duke dispatched a force to besiege San Sebastián while he launched an attack on Madrid, held by the rebel government, which on 23 May withdrew to Seville.

Despite a prior promise of amnesty, the king ordered reprisals against the rebels; in the following years, an estimated 30,000 people were executed and 20,000 imprisoned.

Louis-Antoine, Duke of Angoulême, the victor of the battle, was offered the title "Prince of Trocadero" by the Spanish king, but he refused to accept it, partly in disgust at Ferdinand going back on his promises of clemency.