In the Highlands, especially in the west and north, Gaelic used to be the dominant language and you can still hear it spoken today. As a result of intensive efforts to keep the language alive in speech and writing you will, for instance, find place names in both English and Gaelic on many signposts.
If your ancestors were from this Gaelic-speaking region and you’d like to learn some of this ancient language, an ideal starting point is Sabhal Mòr Ostaig, Scotland’s only Gaelic college. LearnGaelic is also a one stop shop for learning Scottish Gaelic.
For the rest of Scotland, Scots is the predominant dialect though it varies from area to area. The Scottish Language Dictionaries project, a registered charity, will help you explore the language of your ancestors. Another useful resource is the bilingual Scots-Online.
If your ancestors came from the north east of Scotland, especially Aberdeen City & Shire, the dialect they spoke is called Doric.
In Orkney and Shetland, too, you’ll hear a distinctive dialect, at times more Scandinavian than English. These northern islands were once part of the Viking world and many of the dialect words have their origins in Old Norse. Lots of these are still recognisable today, much to the surprise and delight of visitors from Scandinavia.
Once you’ve spent some time in Scotland you’ll begin to pick out dialect differences. Subtle nuances of language that reflect regional identities and strengthen that all-important sense of place. Remember that dialect words are long-lasting and the words you hear today are probably those your ancestors would have used.