Old Scots

Old Scots was a northern dialect of Mid English speaking in parts of Scotland in the while afore 1450. The northern versions of Mid English descended from the Old Northumber. At this time, your speakers called the language of 'English' (in Old Scots: Ynglis or in blackletter 𝔜𝔫𝔤𝔩𝔦𝔰).

Old Scots
𝔜𝔫𝔤𝔩𝔦𝔰
Region	Scottish Lowlands
Era	Developed into Middle Scots by the mid-15th century
Language family	Indo-European Germanic West Germanic Ingvaeonic Anglo-Frisian Anglic Old Scots
Early form	Old Northumber
Language codes
ISO 639-3	–
Any interpretation o the linguistic divide in 1400, based on place-name evidence.   Scottish Gaelic   Old Scots   Norn

Early examples like as John Barbour’s The Brus an Andrew of Wyntoun’s Chronicle are best explaint as part o North Mid English as well as foragners of later Scots. The name Scots was applied they the language until later, in the Mid Scots period.