You need to check out some of his work. He felt that animals were more spiritual than humans and thus closer to nature. Spiritual, not religious in meaning. He was one of the founding members of Der Blaue Reiter (The Blue Rider) which was a group of expressionists who collaborated in Munich Germany from 1911 to 1914.
The name of that movement came from a painting by Russian painter Wassily Kandinsky featuring a landscape which holds a horse and a figure dressed in a blue coat.
Marc was killed in WWII at Verdun but he left an impressive collection of paintings. His animals are simple yet colorful. He gave emotional meaning to colors such as blue for masculinity and power; yellow for female and joy; and red for chaos and violence.
He was toying with cubism and futurism. After he was drafted in 1914 into the German Army he was commissioned to create a military camouflage. He painted canvas in pointillism creating 9 styles borrowing from Manet to Kandinsky.
After the army was mobilized the government identified him as a notable artist who needed to be protected but was hit by a shell before he could be pulled out of service.
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