William de Ros, 6th Baron Ros

William de Ros, 6th Baron Ros, was a medieval English nobleman, politician and soldier. The second son of Thomas de Ros, 4th Baron Ros, and Beatrice Stafford, William inherited his father's feudal barony and estates in 1394. Shortly afterwards, he married Margaret, daughter of John FitzAlan, 1st Baron Arundel. The Fitzalan family, like that of de Ros, was well-connected at the local and national level. They were implacably opposed to King Richard II, and this may have soured Richard's opinion of the young de Ros.