When did the last ice age start in Scotland?

The present ice age started over 2.5 million years ago and we live in a warm interglacial period within that ice age.

The last interglacial ended less than 120,000 years ago, so as far as Scotland is concerned, the last glaciation started about 115,000 years ago.

There was a warm period about 14,700 years ago but glaciers returned at 12,900 years, (Loch Lomond Readvance) and only started warming again 11,500 years ago.