Health secretary Alan Milburn has rubber stamped plans for the trust which will be responsible for social services for adults, as well as GP services and community health services for Northumberland's population of 314,000. It begins work in April.
The care trust is a partnership between the council and Northumberland Health Authority. It will employ around 350 social services staff responsible for assessing people's needs and arranging help, and will take over the day-to-day running of the council's adult residential homes, day care and home care.
Public consultation by both partners has shown widespread support for the move.
Leader Michael Davey (Lab) said: 'This is a momentous event for the council. It took bravery and foresight to get this far and we pay tribute to those who have laid the groundwork for this new and pioneering care trust.'
He added: 'It makes sense for us to work in partnership to provide more integrated services, which will be easier for people to access and understand. The new trust will enable the people of Northumberland to receive the services that best meet their needs and wishes. This builds on the achievements of nurses, social workers and other front-line staff who have already been working in partnership for the last decade.'
Ray Cartwright, professor of cancer
epidemiology at Leeds University, has been appointed chair designate. A chief executive will be appointed this month.
He said: 'Northumberland is leading the way with a new organisation that will benefit not only vulnerable adults and the elderly but also have a positive effect on waiting times and access to services. The organisation is designed to give front-line staff, GPs, nurses and social workers a greater say in how things should be done.'