The present parish of Smisby took its main shape in 1883 when a detached portion of Hartshorne at the eastern end of the village of Smisby adjoining the Ticknall/Ashby road was amalgamated with the parish of Smisby. This parish until the mid 19th century had in fact been a chapelry, although for most of its history a parochial chapelry.

The amalgamation ended a long relationship between the parish of Hartshorne and the parochial chapelry of Smisby, which goes back to the 12th century at least. It probably goes further back to the late 9th or 10th centuries when the new Danish-invaders were settling that part of England which they had seized for themselves, Danelaw, a broad belt of the East Midlands and North East England .

The first written evidence comes from Domesday compiled in 1086, and the earlier history has to be pieced together from Domesday, place-names, what is known of settlement patterns, and what can be deduced from later patterns of relationship between Smisby and Hartshorne (Hartshorne is an Old English name from heorot or heort, a hart or stag, and horn, a horn and is thought to take its name from Horn Hill south east of the village so called from its supposed resemblance to a hart's horn).

Hartshorne lies on the southern edge of the great belt of early Anglian settlement along the Trent basin
Smisby lies a little further south in that part of the Trent basin in which Anglian settlement was late and sparse, but which was heavily settled by the Danes in the late 9th and 10th centuries after the setting up of Danelaw. It lay in heavily wooded country just north of the bleak Ashby Wolds, near the western borders of Danelaw. Smidesbie as it was known in 1086 means the smith's farm. with the second element by the Old Norse for farmstead or village, and the first element Old Norse or Old English meaning smith. Smiths the producers of swords and ploughshares were key figures in both Old English and Old Danish society. Smisby, the smith's home, must have been a tiny settlement in a little woodland glade with small deposits of iron ore surfacing on the site. With iron on the site and nearby woods for charcoal it would be a perfect site for a smith. In 1086 Smisby was held by Nigel de Stafford, and before the Conquest it was held by Edwin. It was not waste, but was only worth half of what it was at the Conquest.

Smisby cut off the main village of Hartshorne from the portion adjoing the Ashby/Ticknall road, yet it itself paid tithe, an ecclesiastical tax to Hartshorne well into the 19th century. Detached portions of counties and parishes normally have their origins in the 10th and 1lth century patterns of lordship and land ownership. It seems very likely that the present village of Smisby was first settled from Hartshorne, the lord of Hartshorne attracted no doubt by the iron.

The original Old English settlers could hardly be left in complete possession of so key a site so near the border of Danelaw and English controlled England. So the Danish settlement was strategically placed to cut off the tiny Hartshorne off shoot from the mother village By.1066 Danes and English were mostly one people, faced by a new conqueror of mixed French and Viking origin, the Normans. The Norman victory at Hastings and the coronation of William I did not end resistance, which continued sporadically through the country for some years. It was put down harshly, and the affected areas wasted and harried by the Normans in reprisal. Apart from the main harrying of the north by William I there is evidence of a very early sweep of harrying across northwest Leicestershire based on a line running from High Grass to Loughborough on the Soar. From the differing states of Hartshorne and Smisby in 1086 it is possible that Smisby was harried on the earlier occasion and Hartshorne on the later.

Smisby in 1086, held by Nigel de Stafford, ancestor of the Gresley family, was assessed in the geld, a fossilised Old English tax of the late 10th or early 1lth century, at 2 carucates, or as much land as could be tilled by two plough teams of 8 oxen each. There was enough arable at the Conquest in 1066 to support 2 ploughs, and now a generation later there were still 2 ploughs, one in demesne, and one shared by 5 villeins or peasant farmers. There was a large extent of wood, half a mile long by six furlongs, which was pasturable. These measurements are probably far from bearing their modern meanings. The statutory mile was only introduced in the mid 19th century. Smisby had however dropped in value from 40s. before the Conquest to 20s. in 1085, suggesting that it had been harried early and that the resettlement and recovery of the arable was only recent or even still in hand. With only 5 villeins sharing a plough, 3 are likely to have farmed 2 bovates each, a very substantial peasant holding which is not reflected in the later history of Smisby so far as can be seen. In more recent times the leading family in the area was Harpur Crewe, who lived at Calke Abbey. They built many of the houses in Smisby (as in nearby Ticknall) for their tennants who worked on the estate, and they exerted a strong feudal influence on the village. In the last few decades the Harpur Crewe estate has been hit by death duties resulting in Calke Abbey transferring to the care of The National Trust as well as many houses and much land being sold by the estate to individual private owners.