The church stands some way from the village, isolated but not austere.
The Norman church survives in the chancel, but in the following centuries the church was enlarged greatly. In the early 14th century transepts were added on the south and north side although these were later demolished in the 17th century. The nave is currently the longest in Northamptonshire and at one time was even longer.
There are many unique features in the church: in the high altar area there is a four-seat sedilia (normally churches only have three seats) indicating that the fourth seat nearest the altar was for the Abbot of Cirencester whose abbey owned the church from A.D. 1133 until the Reformation; there is also a triple piscena in this area; two 13thcentury coffin covers in superb condition are in the south aisle – these were found in the tower in 1981 (probably used by builders as counterweights and left there); a peel of ten bells; 15th century miserichords and 14th century choir stalls. Holy Trinity also has its own imp in the chancel!
Rothwell has had various lords of the manor with their various families involved in the Barons War, Wars of the Roses, Gunpowder Plot, Enclosure Riots and the English Civil Wars. Behind the Crown Inn in Crown Yard was born William Timpson, founder of the famous shoe factory and shop chain; in 1935 at 6 Gordon Street Jim Dale of Carry On fame and narrator of Harry Potter audiobooks was born.
The subterranean charnel chapel houses one of only two remaining in situ medieval ossuaries (collections of human bones) in England. It The contains the bones of hundreds of people, believed to have lived and died between the 13th and 16th centuries. The earliest documented mention of there being a crypt below Holy Trinity church is by John Morton, rector of Oxendon in 1712. In his book ‘The Natural History of Northampton-shire; with Some Account of the Antiquities’ he refers to ‘the great Multitude of Men and Women’s Sculls that lye heap’d up in the famous Charnel-House at Rowel’.
The crypt contains the remains of around 2500 individuals. Local legend suggests that little was known about its existence until the day a hapless gravedigger fell into the crypt whilst working in the church many years ago.Falling some twelve feet through pitch darkness into a mass of bones was too much for the individual to bear, and it is reputed that he lost his mind through the incident, remaining that way until the day he died.
The charnel chapel at Rothwell has inspired researchers for the last 300 years and recently has been part of a joint research project between the University of Sheffield and local people, leading to a website which is linked to below.