Richard's creation as Earl of Cambridge in 1414, however, brought with it no accompanying grant of lands, and according to Harriss, Cambridge was 'the poorest of the earls' who were to set out on Henry V's invasion of France. As a result, he lacked the resources to equip himself properly for the expedition. Perhaps partly for this reason, Cambridge conspired with Lord Scrope and Sir Thomas Grey to depose King Henry and place his late wife Anne's brother Edmund Mortimer, 5th Earl of March, on the throne. On 31 July, Mortimer revealed the plot to the king. Later, he served on the commission that condemned Cambridge to death. Although Cambridge pleaded with the king for clemency, he was beheaded on 5 August 1415 and buried in the chapel of God's House at Southampton. The fleet set sail for France a few days later, on 11 August 1415.