I found this: https://www.nationaldaycalendar.com/april/scottish-american-heritage-month-april without too much difficulty.
Not sure if there is an English or Welsh version, or British. There may well be local ones...
That isn’t mentioned often. Here is what I found: https://upnorthlive.com/news/local/resolution-reintroduced-to-recognize-april-as-arab-american-heritage-month