Original: The New York Knickerbockers were the first baseball team to wear uniforms, taking the field on April 4, 1849 in pants made of blue wool, white flannel shirts and straw hats.
Simplified: Baseball uniforms were first worn by the New York Knickerbockers Baseball Club in the 1800s. Their uniforms were pants made of blue wool, white flannel shirts and straw hats.