'Red' in the Bible

I saw in the night a man on a red horse, between the mountains in the valley, and at his back were horses, red, black, white, and of mixed colours.

In the first war-carriage were red horses; and in the second, black horses;

And the red ones go to the east; and they made request that they might go up and down through the earth: and he said, Go up and down through the earth. So they went up and down through the earth.