I can remember reading that the Broke charity was set up after WWI by an English lady who was in India/ an Arab country (probably the wife of a viceroy or something - can't recall). She had seen a skinny, scabby horse dragging an overladen cart through the bazaar. It stopped for something to be unloaded and as it stood, its poor head drooping with fatigue, it began to tap the ground with a front hoof. It did this in a regular rhythm and she realised where she had seen that before - army horses. The poor horse was asking for a lump of sugar.
She checked and it turned out that she was right. After the war, all of those poor horses which had been requisitioned to serve in the hell of the trenches - farm horses, ladies' riding horses, carthorses, thoroughbreds, plus donkeys - all of them - were deemed too expensive to bring back so were sold off for a song to anyone who would buy them. They then faced lives of hunger and backbreaking work in a climate they weren't even used to - left to be worked to death, in fact.
She was so horrified that the started to Brooke to bring relief to the animals and education to the owners.
It broke my heart too, when I read this, and it continues to break my heart now. Animals aren't there for us to abuse. These aren't their wars, but they suffer in them.