Pierre De Bisschop, 47, is believed to have killed sons Baudouin, 12, and Jean, 20, and his daughter Marion, 18, before shooting his wife Celine, 47 and finally committing suicide.
The gruesome murder-suicide has baffled both authorities and friends, who paint a picture of a happy and financially stable family.
French police were called to the bloody scene in Nouvion-et-Catillon in the Aisne region, roughly 40 miles north of Reims.
De Bisschop's farm workers made the gruesome discovery at around 8.15 am after becoming worried that they had not seen him that morning.
A neighbour and family friend described the couple as 'hard working entrepreneurs' adding that 'the explanation is certainly not financial,' according to Le Parisien.
Pictures of the family on social media include holiday snaps where the siblings are happily posing and hugging each other.
According to a woman claiming to be a friend of the family, the brutal killings took place on Mrs De Bisschop's birthday.
The unnamed friend told L'Union that Mrs De Bisschop had been 'afraid' of her husband.
The De Bisschops had met as students, both attending IÉSEG School of Management at Université Catholique de Lille, France's largest private university.
Mrs De Bisschops had graduated from a private high school in Lille that had been popular with the middle class, according Le Parisien.
His parents meanwhile were farmers, and the couple ended up taking over their business at some point in the late 1990s.
Both Celine and Pierre worked in 'finance' after graduating from university, but when their oldest son Jean was born, the couple bought some land close to his parents in Aisne.
Jean, 20, was a student at the Icam School of Engineering in Lille, while his sister Marion had just enrolled at university to study law.
The youngest son Baudouin was reportedly attending a nearby private school.
Police say they have yet to find a suicide note and have not discovered the reason behind the man's actions.
Pictured: The innocent children killed by their wealthy father before he turned the gun on their mother and himself in French farmhouse murder-suicide Sara Malm for MailOnline 1 November 2017
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