The earliest Irish settlers began arriving in the early 18th century. Initially they were indentured servants who came to work in Boston and New England for five to seven years, before gaining their independence. They were mainly individuals and families, and they were forced to hide their religious roots since Catholicism was banned in the Bay Colony. Then in 1718, congregations of Presbyterians from Ulster in the north of Ireland began arriving in Boston Harbor. They were referred to as Ulster Irish but later were referred to as Scots-Irish because many of them had roots in Scotland. The Puritan leaders initially sent the Ulster Irish to the fringes of the Bay Colony, where they settled places like Belfast, Maine, Londonderry and Derry, New Hampshire, and Worcester, Massachusetts. But by 1729 they were permitted to set up a church in downtown Boston.