Over time, celebrations have been held in spaghetti houses in Ohio, at baseball games in Texas and at a flurry of ceilidhs from Toronto to Salt Lake City. On Saturday, a night of Highland dancing, pipes and genealogy – with a Scottish meat pie and chips included in the ticket price – will be held in Dunedin, Florida.
In New York, the annual parade will roll through 6th Avenue in Manhattan with Dr Who actress Karen Gillen appointed as this year's Grand Master. Sam Heughan, the Outlander actor, and comedian Billy Connolly have done the honours in the past.
Amid the joy, the noise and the sentimentality for those who feel Scotland in their bones, it is also serious economic exercise in promoting the virtues of the motherland. Visit Scotland and organisations representing the Outer Hebrides, Orkney and Shetland are involved, as are Scottish Government people.
Selling Scotland and Scottishness, whatever that looks like, is an important part of Tartan Week business.
At National Museums of Scotland, a new book coincides with the April celebration. Highland Style: Fashioning Highland dress, c.1745-1845 looks at the complex social, cultural and political forces that turned tartan from a marginalised regional garb associated with the warrior Gael to national costume that became an icon of Scotland, and by extension, Scottishness. This week, from New York to Florida, Scottishness may well be expressed differently to how its felt in, say, Newbigging or Forfar, but the forces behind it we share all the same.