In rural communities until the first half of the 19th century most people would travel only occasionally to other parishes and when they did it would usually be on foot, on horseback or by horse and cart.  Before the shift to a more urban economy families would often only move to find work and then relatively short distances would be the norm.  Closely knit extended families were a feature of rural communities with relatives living and working together in close proximity.

It is unsurprising with this rural backdrop that many village marriages will have taken place between a few tens of families and that marriages between first cousins was relatively common and, indeed, often considered more desirable than marriage to non-relatives¹.  It was not until the end of the 19th century, when mobility had become more commonplace and public opinion had begun to change, that the levels of these marriages declined. 

The rate of first cousin marriages in the generation estimated to have married during the 1920s was just 0·32% while in the previous generation more than 1% of marriages were between first cousins².  An earlier study by George Darwin, in 1875, found that 4.5% of aristocratic marriages were between first cousins, 3.5% among the gentry and upper-middle classes, 2.25% in the countryside and falling to just over 1% for all marriages in London.

Queen Victoria's own happy marriage to her first cousin, Albert, may have been seen as promoting these marriages and many Victorian novels featured happy marriages between cousins (Emily Bronte's Wuthering Heights, Bleak House by Charles Dickens and other cousin relationships occur in books or verse by Elizabeth Barrett Browning, Anthony Trollope and others).

In 1861 more than 50% of the residents of Tilney All Saints, near King's Lynn in Norfolk, where some of my ancestors were born and brought up, had been born in Tilney and 90% of them had been born in Norfolk, the vast majority within a 10 mile radius of Tilney.

England was full of villages in which generations of intermarriage had resulted in a community tied together by a complex network of blood relationships¹.

Summary

The following diagram attempts to present some of the complex blood relationships that existed within the Tilney families who appear in my family history:

Sources