I'm not sure that The Lawrence Welk Show ever went beyond Canada and the US, but it was a very popular musical variety show on TV in the 50s through to the early 80s. It was a show that your grandparents watched; very corny, very wholesome. Yet, with the passage of time, pretty much everyone now feels it's safe enough to admit that they watched it too. ;-)
I remember watching it, every Saturday night. My parents liked it and, well, we only had one TV channel, so...
Many years later, it now has a bit of a cult following and is repeated now and then on PBS (public broadcasting service) as there are some real gems. Like this modern spiritual about Sweet Mary and Jeebus: