The settlement at Childs Hill is certainly medieval, possibly the 10th-century settlement Codenhleawe, later called 'Cowhouse'. The earliest known use of the place name Child's Hill is in 1593.
The name is probably taken from a family called Child in the 14th century. The Castle Inn was first recorded in 1751, when Child's Hill was a centre for brick and tile-making run by the Morris family, supplying material for building Hampstead.
Being more than 259 feet above sea level (at the Castle Inn), Child's Hill is visible for miles around. From 1808 to 1847 there was an optical telegraph station, one in a line from the Admiralty to Great Yarmouth. Only the name, Telegraph Hill, remains.
An Act of Parliament in 1826 allowed for the construction of the Finchley Road (completed by 1829) with a tollgate at the Castle Inn. In the early 1850s a Colonel Evans built houses in a field called The Mead, where the Morris brick works had been. The road was later called Granville Road. In 1856 a new church, All Saints', was built. In 1940 the church was so badly damaged by fire that it had to be substantially rebuilt in 1952.
By the 1870s a number of laundries at Childs Hill cleaned clothes for people in the new suburbs of West London and Hampstead. Clothes washed in London were thought to be susceptible to waterborne disease, such as cholera and typhoid, and Child's Hill, then still in the countryside, was supplied by a series of small streams coming off Hampstead Heath.
In 1884 the Pyramid Light Works, a candle factory, was the first factory in the Hendon area. Victorian Child's Hill was a 'very low' place, with cock-fighting, drunkenness and vice. Housing in Child's Hill in 1903 was described as a 'disgrace to civilisation', and in 1914 Hendon Urban District Council built its first council estate, numbering 50 houses.
With the arrival of motorbuses (1906), the tube at Golders Green tube station (1907), the trams (1909), and finally The Hendon Way (1927), farmland succumbed to suburbia.
For entertainment Childs Hill had The Regal in the Finchley Road (1929), which was first a skating rink, then a cinema, then a bowling alley. In the early 1960s many of the small Victorian houses in the Mead and around the Castle Inn were demolished.