The village was populated at the exit of the Mülibachtal surrounding the Alp Mühlebach. It consists of the areas Vorderdorf (earlier called "hinter dem Bach"), Dörfli and Hinterdorf (together once called "Engi vor dem Bach"). The Ratherrenhaus im "Bergen", which was torn down in 1972, probably dates back to the 13th century. Towards the middle of the following century the place name ze engi appeared. The name of the municipality either stems from a term related to a meadow by the Sernf, or it is derived from the term Anger, which means field.
The villages Engi and Matt were parts of the Wahltagwens Matt. A members' index along with armaments for this municipal area dated to 1582 has been preserved. In 1621, the Matt population was obliged to provide assistance following the Engi avalanche. In 1738, the Flittern avalanche buried the house of Hans Baumgartner and ten people died. The Mühlebach corporation was established in 1828. (This stream raged its worst on 15 June 1910) The Tagwen bought Alp Mühlebach from the parish and private individuals in 1843/44 for some 60 000 gulden or 90 000 Francs. The power plant of the Sernf valley railway (1905-1969) was located in a former silk mill in "Wyer". After the avalanche-prone winter of 1998/1999 the municipality had to rely on personnel and tools of the army........more at www.engi.ch