February 1811. For a year, Marshal Victor has besieged the Spanish city of Cadiz. Generals Manuel de Lapeña and Thomas Graham, at the head of the Hispano-British troops, join Algeciras and Tarifa. The contingents, after their disembarkation, move towards Chiclana to take the French from the rear. On March 5, the two armies meet near the Barrosa tower, which will give its name to the battle, and the Bermeja tower. The French troops of Generals Villatte, Leval and Ruffin are gradually pushed back by the British and the Spanish. The commitment of the units and the violence of the fighting were such that the 8th line regiment lost its eagle, crowned by the municipality of Paris a few months earlier. Through his in-depth study of the archives, both French, Spanish and British, and through the discovered and unpublished accounts of the actors of these battles, the author makes us discover a rich and magnificent version of this forgotten and unknown battle of the war of the Peninsula.