Porcuna Plan and Preliminaries of the Battle.
A week after the uprising of May 2, 1808, General Dupont, on his way to Cadiz commissioned by Napoléon to protect the fleet of Admiral Rosily in his campaign to invade Portugal under the Treaty of Fontainebleau agreement between both nations, he sensed that could meet resistance from the Spanish uprising in Andalusia, once his troops reached the town of Andujar Jaen. This resistance came from the organization of some troops from the General Brown in Sevilla, specifically in the town of Utrera.
On June 26, after the Junta of Seville passed reviewed the troops, departed for Cordova and Ecija, completing the same instruction. On July 11, 1808, arrived in Porcuna, established the famous "Plan Porcuna" with the troops of the Kingdom of Granada, creating a Spanish resistance force of nearly 30,000 men and 28 pieces of artillery.
After joining the troops on Seville and Granada Porcuna on 11 July to become the Army of Andalusia, led by General Brown, it was necessary to establish the Campaign Plan, which will be known as "Porcuna Plan". The plan of battle was as follows: The G. Brown versus Andújar, expected to come from the G. Reding Bailen and allowed to form a pincer attack the French on two fronts. But this does not happen at the end.
During the days before the war, 15, 16 and 17 July skirmishes occur with any major clash between the two armies, as happens in Mengíbar, it remains favorable to our troops, killing the French General Gobert, leading their cuirassiers which is replaced by Dufour.
Dupont had left Andujar to Bailen at night from 18 to 19 July. Arrive around three in the morning with his vanguard to bridge Rumble. Wait surprise the Spanish forces bivouacked outside Bailen.
Divisions Coupigny Reding and had settled in Bailen from the morning of 18. Anticipating a possible attack by Vedel, which could approach from the east from the Carolina. Reding seven battalions located between the Cerros San Cristóbal and the Hangman, controlling access to the villa. Done, is prepared to go to Andujar.
From this it follows that both sides were ill-informed about the strengths and positions. Neither knew Reding Dupont approached, or it was going to come up with two Spanish divisions. In addition, Dupont had threatened his rear by Hazel, which could come from Andújar, and Reding feared for his rear, as descended from the Carolina Vedel. It was winning the battle against time; hence the desperation to break through to Dupont Despenaperros and commitment to resist the French action.