Samson has taken over following the retirement of Chris Blanchett last month.
Samson was chief executive of the former Ipswich and Norwich Society prior to its merger with the Colchester and East Essex Society to create the East of England society. Before moving to Ipswich Samson was chief exec of the Heart of England Co-operative Society in Warwickshire.
Samson said he was keen to continue driving forward the society's ongoing development programme.
"I am taking over at an exciting time. Our current development programme involves £40m being allotted to upgrade existing businesses and acquire new ones and is the largest programme ever planned by the Co-op in East Anglia."
The East of England Co-operative Society, with annual turnover in excess of £350m, owns 117 food stores and employs more than 5,000 employees in a trading area that covers Norfolk, Suffolk and Essex.