English dominated Scotland
Apart from the ban on Gaelic and Highland dress for a while, and the Highland Clearances? The latter are not entirely simple, as plenty of the landowners in question were also Scottish. If I may paste a paragraph from Wikipedia:
<blockquote>
With the development of pseudoscientific racist ideas from about 1850, the Clearances were at times supported by belief that the Celtic "race" was inferior to the Anglo Saxon "race".[31] George Combe's popular and influential The Constitution of Man, published in 1828, provided a framework which would be used by some to support theories of racial superiority[citation needed]. In 1850 Robert Knox published The Races of Men which asserted the inferiority of the Celt compared to the Anglo Saxon and Nordic races[citation needed].
The view that the economic failures of the Highlands were due to the shortcomings of the Celtic race was shared and expressed by the two most important Scottish newspapers, The Scotsman and the Glasgow Herald – and even the more northerly Inverness Courier.[31]
In 1851 The Scotsman wrote that
“Collective emigration is, therefore, the removal of a diseased and damaged part of our population. It is a relief to the rest of the population to be rid of this part."
Similar views were held by senior public officials. Sir Charles Trevelyan was co-founder with Sir John McNeill of the Highland and Island Emigration Society.
</blockquote>These days we'd call it ethnic cleansing. Trevelyan was Cornish. McNeill was Scottish.
Perhaps the Scots played such an important role in Empire as they had nowhere else to go?