Old Norse (North Germanic). This evolved into the modern North Germanic language group, of which most except for Norn still survive.
Norn language. This was spoken in the
Orkney and
Shetland islands but was replaced by English/Scots in the 18th and 19th centuries. The last speaker died in the 19th century.
Pictish language (Celtic). Was spoken in wha is now
Scotland in the early Middle Ages by the
Picts. It was replaced by Scottish Gaelic and Old Norse in the 9th and 10th centuries.