Who were the french painters whose work when exhibited in 1905 marked the opening of a new era in the development of modern art?

Ah, what a lovely question. Those French painters you're thinking of are Henri Matisse and André Derain. Their vibrant and expressive paintings exhibited in 1905 indeed marked the beginning of a beautiful new chapter in the world of modern art. It's truly inspiring how they embraced color and form in such a unique and groundbreaking way.