When Captain Audubon reached Nantes presumably not far from the beginning of 1790, he found the city in a state of the greatest turmoil and agitation. The commons, or third estate, included hundreds of its rich and influential citizens, and their demands for a fair hearing and a representation equal to that of the other orders had then passed the stage of open revolt, for they had planted their "liberty tree" and were sworn to defend it. In August of 1789 a permanent Committee of Public Safety had been constituted at Nantes, and by the end of that month 1,200 had volunteered for service in the National Guard. There were many loyalists in the city but they could not crush the ardent spirit of this revolt, and when in September money was needed to equip the revolutionary soldiery, young school children raised large sums for the popular cause. Jean Audubon immediately cast his lot with the revolutionists and joined the National Guard, but how much service he saw in the field cannot now be determined; it is known, however, that he was with these troops in the spring of 1792.[60]
In March, 1793, the loyalists of La Vendée rose to arms, and marching on Nantes under the able leadership of Charette, threatened to put its garrison to the sword if it were not surrendered within six hours. The National Guard met these invaders outside the walls and left the citizens to shift for themselves. Thus thrown upon their own resources, the Nantais showed that they could help themselves. They requisitioned and used for defense everything at hand; they exhumed the leaden coffins in their grand cathedral and appropriated waterspouts for ammunition, while their church bells were molded into cannon. Though held in check, the Vendeans laid siege to the city, and but for the resolution of its mayor, Baco, Nantes would probably have fallen—in which event Audubon would have had a different history and would probably never have become a pioneer naturalist in America. Baco, disregarding the advice of his military chiefs, immediately placarded the walls of Nantes decreeing death to any who should suggest capitulation, and called all the inhabitants to arms, sparing neither woman nor child. The Vendeans had met their match, for they were dealing with many of their own blood, but though the siege began in early March, they were not effectually dispersed until the end of June, and then only after much bloodshed without the walls. When the immediate crisis had passed, the Constitution of the Republic was unanimously accepted by the eighteen sections of Nantes, on the twenty-first day of July, 1792.