 Grey fought for Henry VII against the Yorkist pretender Lambert Simnel at the Battle of Stoke Field on 16 June 1487.In 1491 he was a commissioner to raise money in Bedfordshire for a war against France.On 17 June 1497, eleven years and one day after Stoke Field he again fought in a royal army when it defeated Cornish rebels at the Battle of Deptford Bridge (also known as the Battle of Blackheath).