He was introduced to public life and to court by his neighbour in Yorkshire, George, 2nd duke of Buckingham, was elected M.P. for York in 1665, and gained the "first step in his future rise" by joining Buckingham in his attack on Clarendon in 1667.
The result was that Shaftesbury, Buckingham, Wharton and Salisbury were sent to the Tower.
Here Morton encouraged Buckingham's designs against Richard, and put him into communication with the queen dowager, Elizabeth Woodville, and with Henry Tudor, earl of Richmond.
He escaped from Brecknock Castle to Flanders, avoided Buckingham's fate, and devoted his energies during the next two years to creating a party in England and abroad in the interests of the earl of Richmond.