The original nave and chancel church is of c.1150 and has aisles of 1180, of which two bays survive in each. The church has been extended or adapted over time and now includes an extended chancel, vestry, N chapel, N and S aisles, S porch and W tower.

The church of Kingsbury was given by the first Osbert de Arden to the nuns of the priory of Markyate, otherwise known as Holy Trinity "in Bosco", Co. Beds., and confirmed to them by his son Osbert. The rectory of Kingsbury was divided into two halves during the time of Robert and Amabel (daughter of the younger Osbert), who presented to both of them. After the right of presentation had been returned to the nuns, at some time between 1188 and 1198, one half of the church was confirmed by them on Roger de Coleshill who paid them 20s. a year.