The Parish of South Knapdale was formed in 1734 and churches were built at Achahoish and Inverneill (now a ruin). Achahoish Church was completed  in 1775, rectangular in plan with the square castellated tower added in the 19th century. 

There is a strong local tradition that St Columba came here 1400 years ago on his way to Dunadd and Iona. The ancient baptism font in Achahoish Church is from St Columba's Cave which is further along the coast and believed to be a Stone Age mortar.