Two young ladies escaped to the fresh air of the country to escape the plague of 1645. Being pretty young things, they changed into drab coloured outdoor clothes (including dark green boots?) to avoid the attentions of young men (who could be plague carriers), although their precautions were all in vain.

BETSY BELL AND MARY GRAY

Betsy Bell and Mary Gray,
They were bonny lasses.
They built them a bower on yon burnside,
They theeked it all o'er wi' rashes.

They theeked it all o'er wi' rashes green,
They theeked it all o'er wi' heather.
The plague came from the burrows-town,
And it slew them both together.

They would not have their shoes of red
Nor would they have them yellow.
But they would have their shoes of green
To ride through the streets of Yarrow.

They thought to lie all in the church yard,
Among their noble kin.
But they were laid in Stronach Hall,
All art beneath the sun.

Their lover &/or an errand boy who brought them food supplies also brought them the plague. So they did die.

But why was the shoe colour important?

They would not have their shoes of red
Nor would they have them yellow
But they would have their shoes of green
To ride through the streets of Yarrow.

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