Nap, Originally the Infantry of the Legion wore blue uniforms and pants. Unfortunately the dye used for the uniforms was inferior and the uniforms turned a purplish color after being worn in the field.
These were discarded and the common Green jacketed uniform was adopted.
At least that's what the ledged says.
The Mounted Unit was always in a Green faced buff uniform as far as I know.
Pyles Massacre......A group of Torries (about 200 mounted men) mistook Lee's men for the British Legion and allowed them to ride right up to them. Lee's men proceeded to hack the Torries unmercifully and slaughtered them. Pyle was the Torry Commander. Many considered it payback for Loyalist atrocities.