Poirot meets Hastings almost immediately upon his arrival in England, and the two become life-long friends. Hastings, while being no great detective himself, serves Poirot in many ways. A former British Army officer in World War I, he is extremely brave and often used by Poirot for physical duties such as catching and subduing a criminal. Poirot likes to tease Hastings about being dim-witted at times, but he clearly enjoys the Captain's company. Before Hastings marries, the two men even share a flat.
Hastings represents the traditional English gentleman -- not too bright but absolutely fastidious, a throwback to the Victorian era who is always concerned about "fair play." He is chivalrous, as well, possessing a pronounced weakness for pretty women with auburn hair (a fact that gets him and Poirot into trouble more than once). He eventually marries one of the auburn-haired beauties and moves to a ranch in Argentina, returning to visit Poirot periodically.
See also: Hercule Poirot, Chief Inspector Japp