Patrick Crawley was the only son of James Crawley. His father was the first cousin of Robert Crawley, Sixth Earl of Grantham and heir to Earldom and the family fortune. Patrick worked for the Foreign Office. He often visited his family at Downton Abbey and was well regarded by his family and the servants. There was an understanding that Patrick would wed Lady Mary Crawley. Lady Mary was indifferent to the idea of marrying Patrick despite the family pressure, while her sister Edith was in love with Patrick. He and his father perished in the sinking of the RMS Titanic, at the very beginning of the series.
In 1918, Major "Patrick Gordon", a member of the Princess Patricia's Canadian Light Infantry, made a request to stay at the convalescent home at the Downton Abbey because he claims to be related to the Crawley family. Major Gordon then claims to be Patrick Crawley. He says he survived the Titanic sinking but developed amnesia and took his new surname from a bottle of gin. It is impossible to recognize Major Gordon as Patrick Crawley as his face was severely burned during the Battle of Passchendaele. Gordon does convince Lady Edith by relating experiences in Downton, but decides to leave, rather than commit to his (almost certainly false) claim. It is suggested by the Earl's solicitor, George Murray, that a Peter Gordon might have worked with the real Patrick Crawley at the Foreign Office, which would explain how he knew some of the private details of the Earl's family.