The name Rachub is thought to have come from Yr Achub, which would roughly translates as The Saving or Safe place. The origin of this is the belief that when enemy forces were in the area the locals would flee to Rachub for safety (though the village itself did not exist then), although the story is a myth, an achub in fact being an area of land in Old Welsh. Rachub was considered no more than a part of Llanllechid parish until the 19th century, when the slate industry expanded in the valley, and Rachub grew as a separate village.
Until then, the village consisted of a few houses and the Carmel chapel. Most of the area was farmland, used mostly for sheep. This changed considerably over the last half of the 18th century and the 19th century, with farms giving way to housing. Much of the housing was concentrated in small streets off the High Street. These many ranks of terrace houses are served by a narrow foot lanes connected to the high street. At the top of the village and to the east of the high Street, slate and stone quarry waste heaps prevent further housing development. In the 20th century some new housing has been established in the lower parts of the village especially along Lon Henbarc,
Day to day life 
Welsh is the main language in the village, although it is in decline. In 1991, 83% of residents spoke Welsh. In 2001, Gwynedd council had changed its local ward boundaries, so the figure today is unclear, but is certainly still over 75%. The higher part of the village, which goes up the Carneddau mountains, is more English-speaking, while the lower parts tend towards Welsh.
Most residents commute to work from the village (with very few having the opportunity not to do so), many to Bangor. The main gathering points include the local pub (The Royal Oak or Y Dderwen Frenhinol) and the local post office. Rachub is also home to Ysgol Llanllechid (a Welsh-language primary school), a bakery and has three chapels. Even so, it is generally considered to be a part of Bethesda rather than a separate entity. Villagers will variously say that they are from either Rachub or Bethesda, depending on whichever one takes their fancy at the time.
Though not noted for much, perhaps Gruff Rhys, the Super Furry Animals' lead singer, is its most famous export. The Welsh-language band, Celt, are a very popular band in the Welsh music scene, and hail from the village.
See also 
- Gruff Rhys - BBC guide to the singer
- Ysgol Gynradd Llanllechid - The Welsh primary school in Rachub
- www.geograph.co.uk : photos of Rachub and surrounding area