Born in Chicago, Illinois, O'Connell's youth was altered drastically as his father Jack O'Connell left his family out of shame of being branded as a Medjai when O'Connell himself was ten and shortly after, O'Connell's mother died of unknown causes, leaving O'Connell to grow up in an orphanage in Cairo, Egypt. While in the orphanage, O'Connell was also branded as a Medjai with the trademark tattoo.
Once O'Connell had grown older, he had dedicated time to several adventures alongside his friend and oft accomplice Izzy Buttons, in misdeeds such as bank robbery, but had abandoned this when he enlisted in the French Foreign Legion in an expedition to an ancient Egyptian necropolis known as Hamunaptra, with Rick as one of only two survivors, returning three years later, finding the ancient mummy Imhotep and stopping him from an ascent to power with an archaeologist-turned librarian called Evelyn Carnahan, whom O'Connell had fallen in love with during the expedition, and married shortly thereafter. Imhotep would, however, resurface into Rick's life several more times, causing Rick to defeat him with the help of his own family. Over the years, Alex and Rick's relationship suffered some strains as Alex left his family behind to join the United States Air Force, these strains continuing well on for years until their collaboration in the defeat of the ancient Chinese immortal known as Emperor Han, which led to a reconciliation betwixt father and son.