St. Mary's Bay is one of many bays in Newfoundland, Canada, where bay is taken as a regional subdivision, somewhat along the lines of county divisions (Newfoundland, a largely maritime society, lacks counties). It is the most southern and eastern of Newfoundland's major bays.
It is located on the southern shore of the Avalon Peninsula and is the heartland of the Irish Newfoundlanders, who live all along its shores, stretching west to the Cape Shore and Placentia and northeast to the Southern Shore and St. John's. Like most Irish Newfoundlanders, area residents trace their ancestry to County Waterford, County Wexford, County Kilkenny, south County Tipperary and east County Cork. In addition to being Irish, the region is also overwhelmingly Roman Catholic.
