Ross-shire was named after and covered most of the ancient province of Ross, and also included the Isle of Lewis in the Outer Hebrides.

The boundary between Moray and Ross in the 10th century followed the River Beauly, which also marked the southern extent of Norwegian overlordship at the time.

[4] Another act in 1649 re-stated Ross's separation from Inverness-shire, but was only implemented for the purposes of appointing commissioners (as members of the Parliament of Scotland were called).

Ross-shire also excluded other areas north of the River Beauly owned by Clan Fraser of Lovat, which stayed in Inverness-shire where that family was based, and the Ferintosh estate on the Black Isle, which was owned by the Forbes family based in Nairnshire, and so was made an exclave of that county.

[6][9][8] In the late 17th century, Cromartyshire was significantly enlarged to take over numerous separate tracts of land across Ross-shire.

In 1667 Commissioners of Supply were established for each shire, which would serve as the main administrative body for the area until the creation of county councils in 1890.

From 1860 the commissioners of supply for the two counties were directed to work together on delivering some functions, notably relating to prisons.

In 1975, Ross and Cromarty was itself replaced by the Highland region and the Western Isles, under the Local Government (Scotland) Act 1973.

Western Ross-shire, also known as Wester Ross, is typified by its mountainous Highland scenery, especially the Torridon Hills which includes such peaks as Beinn Eighe and Liathach.

The west coast of mainland Ross-shire onto The Minch and Inner Sound (opposite Skye), is heavily indented with sea lochs and peninsulas.

[20] The eastern half (Easter Ross) is generally flatter, and consists of towns, villages and farmland bordering the Moray Firth.

The larger inland lochs are:[a] Ross-shire included the northern parts of the Outer Hebrides, in particular the Isle of Lewis.

Due to its flatter, more fertile land, Lewis contains three-quarters of the population of the Western Isles, and the largest settlement, Stornoway.

The only other island in the Outer Hebrides that was in Ross-shire prior to 1889 and was inhabited at the 2011 census was Great Bernera, which is linked to Lewis by a bridge.