When Oliver Cromwell and the Puritans came to power in England in 1647, the celebration of Christmas and singing carols was stopped. However, the carols survived as people still sang them in secret. Carols remained mainly unsung until Victorian times, when two men called William Sandys and Davis Gilbert collected lots of old Christmas music from villages in England.
Before carol singing in public became popular, there were sometimes official carol singers called ‘Waits.’ These were bands of people led by important local leaders (such as council leaders) who had the only power in the towns and villages to take money from the public (if others did this, they were sometimes charged as beggars!). They were called ‘Waits’ because they only sang on Christmas Eve (This was sometimes known as ‘watchnight’ or ‘waitnight’ because of the shepherds were watching their sheep when the angels appeared to them.), when the Christmas celebrations began.
Also, at this time, many orchestras and choirs were being set up in the cities of England and people wanted Christmas songs to sing, so carols once again became popular. Many new carols, such as “Good King Wenceslas,” were also written in the Victorian period.
“Good King Wenceslas” is a popular Christmas carol that tells a story of a king braving harsh winter weather to give alms to a poor peasant on the Feast of Stephan (December 26, the day after Christmas). (Wikipedia)
New carols services were created and became popular, as did the custom of singing carols in the streets. Both of these customs are still popular today! One of the most popular types of Carols services are Carols by Candlelight services. At this service, the church is only lit by candlelight and it feels very Christmassy! Carols by Candlelight services are held in countries all over the world.
via The History of Christmas Carols — Christmas Customs and Traditions — whychristmas?com.