Fleet Grade I listed Anglican church, dating from the late 12th century, is dedicated to St Mary Magdalene. The 120 feet (37 m) church tower with spire is detached from the nave by 15 feet (4.6 m). The fabric is mainly Decorated in style, with Early English arcades and a Perpendicular west window. According to Cox (1916), the church was restored in 1860, when the chancel was rebuilt, although the canopied sedilia was retained. In 1964 Pevsner noted 1798 repairs and considered the church "over-restored". He dated a chancel rebuild to 1843, questioned if it was "done correctly", and recorded Victorian tracery in the aisle windows, a blocked doorway to a previous chapel in the chancel, "fine busts of great variety", a Decorated-style sedilia and piscina with ogee arches and crocketed gables, a reredos dated 1790, and a defaced 14th-century effigy.
Pevsner also recorded an 1854 red-brick rectory designed by Benjamin Ferrey, and a motte south-west of the village where 11th- and 12th-century pottery has been found. The English Heritage record for the now ploughed-down motte site details finds from the Iron Age to the 18th century.
In the 2011 UK census Fleet had a population of 2,136. The parish includes the hamlet of Fleet Hargate.
Lincolnshire is very low-lying and land had to be drained for agriculture to be successful. The larger drainage channels, many of which are parallel to each other, became boundaries between parishes. Many parishes are long and thin for this reason.
There is much fenland in Lincolnshire, particularly in the Boston and Horncastle areas. Fenlands tended to be extraparochial before the mid 1850s, and although many sections were identified with names and given the title "civil parish", little information has been found about them. Many appear to be abolished in 1906, but the parish which adopts them is not given in A Vision of Britain through Time. Note the WR category Lincolnshire Fenland Settlements which is an attempt to organize them into one list.
From 1889 until 1974 Lincolnshire was divided into three administrative counties: Parts of Holland, Parts of Kesteven and Parts of Lindsey. These formal names do not fit with modern grammatical usage, but that is what they were, nonetheless. In 1974 the northern section of Lindsey, along with the East Riding of Yorkshire, became the short-lived county of Humberside. In 1996 Humberside was abolished and the area previously in Lincolnshire was made into the two "unitary authorities" of North Lincolnshire and North East Lincolnshire. The remainder of Lincolnshire was divided into "non-metropolitan districts" or "district municipalities" in 1974. Towns, villages and parishes are all listed under Lincolnshire, but the present-day districts are also given so that places in this large county can more easily be located and linked to their wider neighbourhoods. See the WR placepage Lincolnshire, England and the smaller divisions for further explanation.