What were the causes and the effects of the French Revolution? The major cause of the French Revolution was the disputes between the different types of social classes in French society. The French Revolution of 1789-1799 was one of the most important events in the history of the world. The Revolution led to many changes in France, which at the time of the Revolution, was the most powerful state in Europe. The Revolution led to the development of new political forces such as democracy and nationalism. It questioned the authority of king ....