Despite the idyllic descriptions of Mexico that Maximilian and Charlotte wrote to their relatives in Europe, it did not take long for them to realise the insecurity and disorder which plagued their Empire. Their residences were perpetually monitored by a large armed guard intended to push back the rebel bands which roamed nearby. French intervention, supported by the Belgian and Spanish contingents, was followed by a long civil war which disrupted every aspect of Mexican life. The approximately 30,000 to 40,000 soldiers of the French expeditionary force, led by Marshal Bazaine, had to counter multiple skirmishes led by the guerrillas over a territory four times larger than that of France.