Hartford-based St. Francis and Michigan-based Trinity Health have announced a merger, effective immediately.

St. Francis Hospital and Medical Center, Mount Sinai Rehabilitation Hospital and other St. Francis entities will provide care under the umbrella of the new Trinity Health region in New England, as will the Sisters of Providence Health System in Springfield, Massachusetts, and its subsidiaries.

Christopher M. Dadlez, president and CEO of St. Francis Care, immediately assumes the role of president and CEO of the new, yet-to-be-named New England region.

Daniel P. Moen will continue to serve as president and CEO of the Sisters of Providence Health System, while also having a significant role in the regional system.

St. Mary’s Health System in Waterbury, along with Johnson Memorial Medical Center in Stafford Springs, also aim to join the new region. The new regional health system will embody all participating organizations’ shared commitments to Catholic values and high-quality, high-value health care. It will combine its members’ strengths in inpatient, outpatient and continuing care settings to better serve patients.

“This is an historic day for St. Francis, our patients, employees, physicians and community,” said Dadlez in a statement. “Our aligned mission, vision and core values have guided this alliance since the inception of our discussions and we are confident that together, Trinity Health, St. Francis and the region’s other partners will deliver the greatest opportunities for providing the compassionate, transformative care that will make us the most trusted health partner for life.”

“We partner with organizations that share our commitment to excellence and people-centered care as part of a very deliberate strategy,” Scott Nordlund, executive vice president of growth, strategy and innovation for Trinity Health, said in a statement. “We’re glad to welcome St. Francis to our health system today and look forward to all that our work together can accomplish.”