This is just a guess, but it might refer to the time when the Church of England tried to force the churches (including those in Scotland) to adhere to the practices of the Church of England, which was very similar to the Catholic Church in practice. In a historical drama I saw about Oliver Cromwell, there is a scene where he gets angry and pushes golden candle sticks, cross, etc. off the altar of a Puritan Church and the minster says it was not his own doing that the golden candle sitcks were palced there, but he was only following orders. Cromwell later plans to go to America to be rid of the catholic influence on the church of England. He ends up staying and being a leader in the civil war. But, others might have immigrated during the same period as protest of the practices of the church.