On 20 September 1792, the French won a battle against Prussian troops near Valmy and the new National Convention replaced the Legislative Assembly. From the start the Convention suffered from the bitter division between a group around Robespierre, Danton and Marat referred to as 'Montagnards' or 'Jacobins' or 'left' and a group referred to as 'Girondins' or 'right'. But the majority of the representatives, referred to as 'la Plaine', were member of neither of those two antagonistic groups and managed to preserve some speed in the convention's debates. Right away on 21 September the Convention abolished the monarchy, making France the French First Republic. A new French Republican Calendar was introduced to replace the Christian Gregorian calendar, renaming the year 1792 as year 1 of the Republic.