The Imperial Guard served with distinction in both the Crimean War and the Second Italian War of Independence of 1859, It did not participate in the Mexican Expedition of 1863-67 but remained on garrison duty in Paris. During the Franco-Prussian War of 1870 the Imperial Guard was present at the Battle of Mars-la-Tour, Battle of Gravelotte and the Siege of Metz. Although an elite corps which now numbered over 20,000, the Guard did not perform up to expectations in 1870. This was mainly due to poor judgement on behalf of its commanders, who at Mars-la-Tour committed guard units piecemeal rather than as a single entity in the tradition of the First Empire. At St. Privat two days later, the Guard was held back from battle by General Charles Bourbaki, to the bitterness of the line troops in the front line.