what's the meaning of "cavalry charges"?

When you post a question like this, you need to provide the sentence in which you have read the expression, so that someone can tell you what it means in context. Cavalry are soldiers on horse back. A cavalry charge is an attack by a body of soldiers on horse back. It is usually depicted as the men spurring their horses to a full gallop (i.e., the horses are running as fast as they can), but that is false. In order for an organized body of mounted soldiers to remain organized while attacking, they need to keep their horses under control--and that means that most cavalry charges were conducted at a walk, until close to the enemy, at which time the horses would be urged to a trot, and then to a canter (both terms refer to increasing speed on the part of the horses). The effectiveness of a cavalry charge derives from the troops arriving at the target in an organized body, and using the weight and the moementum to break up the enemy's formation. The Prussians managed a "charge at speed," in which the horses were urged to a gallop (their fastest speed) just before contact with the enemy line--but this was only possible because of a high degree of discipline, expert horse handling and intense training of both men and horses. It was uncommon.

The last successful cavalry charge was carried out by the Canadians against the Germans in Moreuil Wood in 1918 during the Great War in Europe. The Canadians suffered heavy casualties--300 men killed and 800 horses killed--but they did manage to stop the German advance. The last cavalry charges took place in Poland and Russia in the Second World War--but they were not successful.

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