There have long been several versions of how Pe Ell was named, none of which can be authenticated.
One of those versions, and the more accepted one, is that the name comes from the attempts of the local Indians to pronounce the first name of an early French-Canadian settler, Pierre Charles, who was an ex-Hudson Bay employee. This version has it that the Indians could not pronounce Pierre, and their attempts turned it into Pe Ell. Another version is that P and L were the first initials for Pierre Charles and his Indian wife. Two words were made from the initials: “Pe Ell”. Another distinct version is that Charlie Pershell, a Frenchman, settled in the area and married an Indian maiden. The Indians found it difficult to sound out the “sh” in Pershell so it became Pe Ell. In 1897, the North Pacific Railway built a railroad depot in the town. In 1907 Pe Ell’s population was around 1,000 — larger than it is today. The rich agricultural and timber resources of the region attracted farmers, millworkers, and loggers. By 1909, the town had a bank, three dry goods stores, two general stores, three grocery stores, two barber shops, five saloons, four hotels, a newspaper, a blacksmith, and even an opera house.
Pe Ell was officially incorporated on March 9, 1906.
(excerpt from wikipedia)