Short answers, pulled from the story.
The word originally referred to the Gaels of Ireland, not Scotland. The Venerable Bede used the Latin Scottorum to describe the Gaelic people from Ireland who settled in the western edge of what became Scotland, in the Kingdom of Dál Riata. Over centuries, the term shifted to describe all inhabitants of Scotland.
Canada has the highest level of Scottish descendants per capita in the world. According to the 2011 Census of Canada, 4,714,970 Canadians, or 15.10% of the total population, claimed full or partial Scottish descent. Canada is also the second-largest population of Scottish descendants after the United States.
An estimated 40 million people worldwide claim Scottish ancestry, compared to Scotland's own population of just over five million. Large concentrations are found in Australia, New Zealand, Canada, the United States, and elsewhere in the United Kingdom.
Scottish people emerged from an amalgamation of the Picts and Gaels, who founded the Kingdom of Scotland in the 9th century. Celtic-speaking Cumbrians and Germanic-speaking Angles followed, then Norman nobles during the 12th-century Davidian Revolution, then the Norse-Gaels of the Western Isles in the 13th century, and finally the Norse of the Northern Isles in the 15th century.
A 2005 report by the Registrar General for Scotland, based on the 2001 UK Census, found about 92,400 people, or 1.9% of the population, able to speak Gaelic. The number able to read and write it rose by 7.5% and 10% respectively in that census period.
Scottish merchants and traders had been settling in Poland since at least the mid-16th century, drawn by commercial opportunity. King Stephen's Royal Grant of 1576 gave Scottish immigrants royal protection and a district in Kraków. By the 17th century, an estimated 30,000 to 40,000 Scots lived in the Polish-Lithuanian Commonwealth, many coming from Dundee and Aberdeen.