The Last Cavalry Charge... well, one of the last anyway

Oh, the glamour...

The glorious and nostalgic title of last cavalry charge in the History is a coveted one. A lot of it is the glamourization of What Was Before, and what the Cavalry represented then : nobility, richness, honour, bravery... There was also a hint of nostalgia for when the sheer will and momentum was overpowering any accuracy or mechanical engineering : where a Man, as defined by machismo, was enough to defeat its adversary. Hence the association of cavalry charges with sabers and lances, which, of course, the last ones were not likely to involve.
There is something nicely old-fashioned about chivalry, as if it could define a personality as pertaining to a Golden Age (seen in a golden-age primitivism of civilization stripped of its vices, in this case, military civilization), and hence his or her superiority to the baseness of his or her own time. Chivalry was, after all, based on the principle of higher, long-lost morals and standards, and gave the two meanings in "gallant" : "valiant, bold, nobly resolute" in English, "courteous, stylish, charming (towards women)" in French.
I connect that glamour to the same kind of nostalgia and absence of critical reading of the Colonial Era that I had a whiff of in yesterday's movie, Le Crabe-Tambour. Most of this glamour comes from the wars of conquest and of defense against anti-colonialism, ignoring everything of the dehumanization, the greediness, and the disregard for human value that constituted the actual colonization.
I also think that the combination of man and horse, the possible collaboration of the human and the animal reconciling culture and nature, has been fascinating a real deep part of the human psyche, Seabiscuit-style, as would also a touching story about a Marine and her dog saving comrades together.
The Battle of Agincourt, the Charge of the Light Brigade are some of the consequences of the strong belief that a dashing, brave and determinate push of man and horse could not be allowed to fail by God or military logic.

best candidates for the Last Charge, depending on the definition of last charge and cavalry

• the Polish cavalry charging Wehrmacht tanks during the Invasion of Poland in 1939 is the most famous and glamorous Hail Mary example, but is apocryphal : Polish cavalrymen didn't charge tanks (some Soviet cavalrymen did), but they charged infantry. They were mostly successful. And both Polish and German cavalrymen were used to charge. That lingering picture of horsemen being mauled by modern weapons is actually a piece of propaganda from the Nazi regime, depicting Poles as an underdeveloped, medieval army. It survived in the collective consciousness, as did many myths of the Nazis that their enemies where quick to pick up.
• for example, the battle of Krasnobród in 1939 during the same campaign was probably the last engagement in History where cavalrymen charged opposing cavalrymen.
• another "last cavalry charge" saw the Itlian Savoia Cavalleria charge the Russian line with sabers and grenades near Volgograd. A Wehrmacht officer that had witnessed it had to say "Colonel, these kinds of things, we cannot do them anymore".
• the Polish charge at Schönfeld in 1945 may very well be the last cavalry charge in recorded History, and it was successful
• Bersheeba is a famous episode of WWI where Australian mounted infantry (ie : riflemen traveling on horse but fighting usually on foot) overrode (literally) an Ottoman garrison in 1917.
• the taking of Guerrero in 1916 during the Punitive Expedition against Pancho Villa has been dubbed "the last true cavalry charge", mainly because it was made by US soldiers, because it doesn't overqualify the other events of this list, and was quite a miser's success anyway
• the American did make one of the last cavalry charges in History during WWII on the island of Bataan, but as it was during the Pacific War, it stayed mainly undocumented and unsung.

Silver Helmets and Shiny Rides

The one I read today wasn't one of the Last Cavalry Charges, but the First One of WWI. This Battle of the Silver Helmets opposed the Belgian army and the invading Deutsches Heer during the 1914 invasion of Belgium. It participates in rehabilitating the Belgian army, popularly pictured as wiped off the face of Earth in a jiffy before the French and English could stop the Germans on the Somme, although the Belgians, given their little number and their position at the tip of Germany's enemy territory, did quite good.
Liège was the scene of the first strong opposition to the German advance, as it was the easternmost well-fortified place. The strategic aim of this opposition was both to try and save some Belgian territory, but was first and foremost to try and keep the German busy up North so that they wouldn't have their hands free in France and Russia. And it worked. If the Belgians hadn't kept the Germans busy, the latter could have reinforced their lines in France, the French counteroffensive on the Marne couldn't have been conducted and Paris would have certainly fallen -- hence no trench warfare, and hence, no WWI as we know it.
Before Liège got overpowered, the Belgians tried to stop or slow down the Germans. It's during this stand that the Belgian and German cavalries clashed at Haelen, but only the Germans were mounted. The Belgians were dismounted, fortified in a good position, and won the engagement.
The brigade is destroyed.... Rode in against infantry, artillery and machine-guns, hung up on the wire, fell into a sunken road, all shot down.
— Maximilian von Poseck

To put it into perspective, in August 1914, Cuirassiers's primary equipment were still sabers, steel breastplates and shiny helmets. The German Uhlans had lances.
Another point of note is the presence of cyclists among the Belgian troopers. Bicycles are not something we imagined were big with armies, but they were extensively experimented with as a mount for infantry and cavalry from c. 1886 to the end of WWI, especially in Belgium and the Netherlands were they were regular troops, not specialists as in other armies. The Japanese used them again during their invasion of China, and the Germans during their invasion of Poland. The last regular armies to be trained with bicycles are the Finnish, after the Swiss discontinued their own detachment in 2001.