The first step towards the construction of the St. John of God Hospital was taken in 1943 by the Hospitaller Order of St. John of God, which had in mind the construction of a building or monument dedicated to its patron saint, St. John of God, in its birthplace.
Hence, construction began on the building that was eventually transformed into a hospital for sick and poor children in 1947. The Hospital was opened on 3 October 1950, and at the time it was called the St. John of God Children's Hospital, as it was dedicated to sick children.
On the opening day, the relics of St. John of God were carried through the town of of Montemor-o-Novo, coming from Granada, and then were taken to Lisbon for the Commemorations of the 4th Centennial of the Death of the Saint. It was also during this time that the Church of St. John of God was built. It is located next to the Hospital and, to this church, many patients, their families and friends go to ask for spiritual guidance and feel the presence of St. John of God.
With the generous aid of the Calouste Gulbenkian Foundation, the new Hospital was opened in 1966, as well as a Hydrotherapy Service in September 1969.
The Hospital has been a leading name in Physical Rehabilitation, as it has a gym, electrotherapy and orthopaedic workshops for the production, adaptation and maintenance of prosthetics, orthotics and orthopaedic footwear. It is worth mentioning that, in Portugal, there is no other Hospital Institution with all these integrated areas.
This Hospital has been established for more than half a century and during all this time it has been renewed and adapted to the needs that have arisen in our society. During these years, our population has grown exponentially and it is now adults who benefit more from this Institution instead of children, as it was its initial design. For all these reasons, in November 2004, the name St. John of God Children's Hospital was changed to St. John of God Hospital.
Since November 2009, the Hospital has been part of the National Integrated Continued Care Network, with a Continued Convalescence Care Unit and a Palliative Care Unit.
In 2016, a Medium-term care and Rehabilitation Continued Care Unit and a Long-term care and Maintenance Unit were integrated, both also under the RNCCI.
It also has a Rehabilitation and Maintenance Unit for patients, which began operating after the definitive suspension of surgery in 2014.
The St. John of God Hospital is one of the Hospitals of the St. John of God Institute, a non-profit charitable entity that belongs to the Portuguese Province of the Hospitaller Order of St. John of God. Therefore, it is defined as a Catholic Hospital in its identity, purpose and action.