It is a 2nd class municipality in the province of Pangasinan, Philippines.
According to the latest census, it has a population of 74,005 people in 12,690 households.
The town used to be called Angio, and has been the favorite place for rest and recreation of the Dominican Order. It is named after St. Fabian who is also a pontiff and a saint of the Roman Catholic Church. During early 18th Century around 1818 San Fabian had a boundary dispute with Mangaldan considering that the boundaries between the two towns was merely the Angalacan river which sometimes overflow because of the floods. It was only during sometime 1900 that the boundary dispute was patched up when the mayor of San Fabian agreed to meet the mayor of Mangaldan and the two reached an agreement with a boundary marker being erected at Longos between the towns of San Fabian and Mangaldan. The agreement was signed by Juan Ulanday, Nicolas Rosa, Vicente Padilla, Marcelo Erfe, and approved by the American Commander Capt. Ferguson.
The Pangasinan people, like most of the people in the Malay Archipelago, are descended from the Austronesian-speakers who settled in Southeast Asia since prehistoric times. Genetic studies locate the origin of the Austronesian languages in Sundaland, which was populated as early as 50,000 years ago. The Pangasinan language is one of many languages that belongs to the Malayo-Polynesian languages branch of the Austronesian languages family.