Information source: Wikipedia: Counties of Scotland, Wikipedia: Subdivisions of Scotland

1889:

• Ross-shire and Cromartyshire merged into Ross and Cromarty

1890-1975:

• 33 original counties (incl. Orkney and Shetland)

1975-1996:

• Replaced by 12 regions (incl. Orkney and Shetland)

1996:

• Replaced by 32 Council Areas (Unitary Authorities)