The English ordered the French prisoners executed because they feared their baggage train would be overrun. Sorry, but I don’t have much sympathy for the French.
By the way, although Henry is usually recognized as the hero of Agincourt, one of his most successful commanders had been the First Earl of Shrewsbury, Sir John Talbot, who led the forces at Harleur, the precursor to Agincourt.
And the French would cut off the index and first fingers of captured English bowmen.....those with 2 first fingers would wave them at the French....the V salute.