In 1894, Frederick Philip Chamberlain (1866 - 1952) moved from Soley Farm, near Ramsbury in Wiltshire, to Crowmarsh Battle Farm in Oxfordshire, taking over from the Newton family who had been there for over 100 years, farming sheep and cattle. By 1909 all the livestock had been sold and the farm became entirely arable. He established the "Chamberlain System", as it was referred to in agricultural journals, whereby corn, particularly barley, was grown continuously over many years, undersown with a trefoil/ryegrass mix, with the land having only a few "rest periods" in between corn crops.

His son, Philip Charles Chamberlain (1913-1975), knew from an early age that he wanted to be a farmer. He served his farming apprenticeship, firstly with Mr S Farrant at Clifton Hampden from 1930 for about three years, followed by later periods with Mr T Hedges at Fulscote and Mr F Swanton near Marlborough, returning home permanently in 1935. He is first recorded in the farm's wages' book at the age of 11, and again in 1933 as a manual worker of whom his father wrote, "When PCC started his manual work I reckoned that he was approximately equal to one-and-a-half men". In 1936 he formally joined his father in the management of the farm, sharing in the profits and farming decisions. His major contribution to the farm's development was to more than double the size of farm from 480 to 985 acres with an additional 325 acres rented. He also oversaw the transfer of the business from a family partnership to a limited liability company. Like his father, he served on Benson Parish Council for most of his adult life.

The farm is now managed by his grandson, Philip Walter Chamberlain (b1951) who knew from an early age that he too wanted to be a farmer. Educated locally at first, then Dean Close Cheltenham, followed by Berkshire College of Agriculture, Philip did his year's practical experience at Mr Bob Beacroft's farm at Moulsford. Philip began working full time at Crowmarsh Battle Farm in 1973, becoming a Director in 1975 and Managing Director in late 1975 on the death of his father. He too has considerably changed the farming system, by introducing crops encouraged by European policies and by greatly increasing the acreage farmed on contract from neighbouring landowners. The introduction of new technology has allowed the farm records to be computerised and crop yield maps to be produced using the Global Positioning System.

In 2011 Philip's eldest son Tim (b1983) came back to the farm having trained and practiced as a Landscape Architect, to be joined by his younger brother Charlie (b1985) in 2012, following training and working as a Civil Engineer. Tim studied for a Post Graduate Diploma in Agriculture at the Royal Agricultural University whilst Charlie studied an MSc in Rural Land and Business Management at The University of Reading.