It was not until 1295 that Edward I became aware of the secret Franco-Scottish negotiations. In early October, he began to strengthen his northern defences against a possible invasion. It was at this point that Robert Bruce, 6th Lord of Annandale (father of the future King Robert the Bruce) was appointed by Edward as the governor of Carlisle Castle. Edward also ordered John Balliol to relinquish control of the castles and burghs of Berwick, Jedburgh and Roxburgh. In December, more than 200 of Edward's tenants in Newcastle were summoned to form a militia by March 1296 and in February, a fleet sailed north to meet his land forces in Newcastle.