 Sir Henry Sidney, the former Lord Deputy of Ireland influenced the response from his membership of the Privy council and in August 1580 a new Lord Deputy, Arthur Grey, 14th Baron Grey de Wilton was sent from England with 6000 troops.Grey's immediate priority was to put down the Leinster rebellion.On 25 August 1580, English forces under Grey were routed in the Battle of Glenmalure with the forces of O'Byrne and Viscount Baltinglass.