A Spanish and German surname, Armacost referring to the eagle as a host. Variations in spelling Armacost are Armagost and Ambercoss. In Germany there were large populations of Armacost families. They would be the ones to later come in the 1700s to resettle in Maryland and Pennsylvania. Within the United States the main concentration of Armacost families are in Maryland, Virginia, Pennsylvania, Indiana and Ohio. Famous: Peter H. Armacost (former President of Eckerd College and contributed to building a library at Eckerd College), Michael Armacost (international diplomat) and George H. Armacost (President of the University of Redlands in California for 25 years).