Vikings first landed in Shetland and Orkney Isles in the late 8th Century with further onward migration following as the islands became overpopulated.
The island of Hoy, Orkney. Its name is derived from the Old Norse for High Island. The arrivals, first pillaging and plundering, became more peaceful over time with their culture and language starting to leave their trace on their new homeland.
Orkney island of Hoy - the last land which separates Orkney from the Atlantic - derives it name from the Old Norse word ‘háey’, with Hoy translating as High Island. Meanwhile, Lerwick translates as ‘muddy bay’ and Kirkwall as ‘church bay’.
Vikings are also known to have pulled their boats out the water and over land to shorten journey times and avoid unnecessary danger.
Old Norse place names are of great interest e.g. Lerwick in Shetland, translates as Muddy Bay. Eday in Orkney translates from the Old Norse for Portage Island. It was places such as Eday that Viking boats, with their low keels, could sail right onto a beach and a large crew could drag their ship across land to shorten travel time and journey distance. The Viking boats were really, really light and they could be pulled across land really easily. The Vikings created short cuts. When the Vikings were in Russia and coming down the rivers, hitting lots of rapids, they would get out the boat and walk.
These boats were so light that they could be pulled for around a kilometre without much effort. Small ships were sometimes put on wooden poles and carried by the crew with larger vessels sometimes moved on rollers.
At Loch na h-Airde on the Rubha an Dunain peninsula on Skye, in 2009, archaeologists discovered early 12th Century boat timbers, a stone-built quay in the loch and a system to maintain a constant water level to allow boats, likely birlinns, to enter the sea at high tide. It is believed that this site, which served as a significant anchorage for the western seaboard will yield further remains of Norse and medieval vessels potentially lying in the loch.
The Viking invasions of Scotland occurred from 793 to 1266 when the Scandinavian Vikings - predominantly Norwegians - launched several seaborne raids and invasions against the native Picts and Britons of Scotland. The invasions began when the Vikings sacked the monastery of Iona in 793, and, during the 9th century, the Vikings established kingdoms such as Sudreyjar (also known as the "Kingdom of the Isles"), Orkneyar, and Gallgoidel in the isles to the north and west of Scotland. In 839, King Eogan mac Oengusa of Fortriu and King Aed mac Boanta of Dal Riata were slain in a major defeat from the Vikings. In 837, 845, and 847, the Viking chieftains Soxulfr, Turges, and Hakon launched seaborne raids from their well-established dbases in northern Scotland.
In 847, the Vikings conquered the Inner Hebrides from the native Picts, and many Norsemen intermarried with Pictish women, leading to the formation of the syncretic "Gallgoidel" (Norse-Gael) culture. By 878, both Kintyre and the Isle of Man had fallen to the Vikings and were being used as bases for further raids.
The Vikings of the "Kingdom of the Isles" launched devastating raids not only on Scotland, but also on Ireland and England, and, in 872, they destroyed the Briton kingdom of Alt Clut's stronghold at Dumbarton, leading to Alt Clut transitioning into the "Kingdom of Strathclyde". The Viking leader Ivar the Boneless - who had commanded the assault on Dumbarton - died in battle with the Irish in 873, but his descendants, the Ui Imair, continued to rule over both Sudreyjar and Dublin and eventually conquer Northumbria.
The Pictish kingdom of Alba took advantage of the chaos of the Viking invasions to unify the Gaelic kingdoms under its banner and form the Kingdom of Scotland. King Constantine I of Scotland was killed in battle with the Vikings in 877, but his successors such as Giric would extend Scottish power to Bernicia in the south (expelling the Northumbrian magnates from Lothian), only for King Guthred of Northymbre to ally with the Anglo-Saxons and repel a Scottish invasion of Northumbria. During the reign of Donald II of Scotland (r. 889-900) - who abandoned the title "King of the Picts" and bore the title "King of Alba", the Northmen wasted Pictland, but the Scots defeated an invading Viking army at Innisibsolian. Under Donald's successor Constantine II of Scotland (r. 900-943), the exiled Dublin Norse attacked his kingdom in 902, but they were defeated at Srath Erenn, and, in 904, the Picts of Fortriu defeated and slew Imar ua Imair in battle. Starting in 914, more Viking fleets began to appear in the Irish Sea, and, by 916, the fleets of Sihtric Caech and Ragnall ua Imair were very active in Ireland. In 918, the Dublin Norse invaded Northumbria with the goal of exploiting Lady Aethelflaed of Mercia's death, but they were fought to a draw by the Scots and Northumbrians at the Battle of Corbridge. The Vikings ultimately took York in 919, and, in 920, the Vikings of York swore fealty to King Edward the Elder of Wessex. By 926, however, Edward was dead and Sihtric - now a Christian and the husband of Aethelflaed's sister - rebelled against Edward's successor Aethelstan of England. Constantine allied with the Vikings, leading to Edward marching against him in 934. In 937, at the Battle of Brunanburh, Aethelstan defeated the Vikings and Scots, but, following Aethelstan's death in 939, Ragnall ua Imair retook York and restored Danish rule in Northumbria. Under King Indulf (r. 954-962), Lothian fell to the Scots, but he was killed by the Vikings at the Battle of Bauds in 962. During the late 10th century, Scotland suffered from internal strife, and the Norse suffered from similar issues; by 977, Earl Sigurd Hlodvirssor of Orkney was caught up in fighting against the Kings of Moray. There was a tense peace between the Norse and Scots from the 970s to the 1090s, as the House of Alpin's rule strengthened in Scotland, and the Scandinavian threat decreased due to infighting.
The King of Norway Magnus Barelegs succeeded in bringing Sudreyjar under Norwegian rule in 1098, taking Orkney, northern Scotland, and the Hebrides after "dying his sword red in blood". King Edgar of Scotland responded by making peace with the Norwegians, recognizing their control over the Northern Isles. The descendants of Godred Crovan restored Sudreyjar's independence, only for Somerled's death in battle with the Scots at the Battle at Renfrew in 1164 to lead to restored Norwegian rule. In 1209-1210, the Norwegians raided Iona in what was sometimes called "the last Viking raid". From 1263 to 1266, Norway went to war with Scotland over a border dispute concerning the Hebrides, and, in 1263 - in what the BBC called "the last battle of the Vikings" - the Scots defeated the Norwegians at the great Battle of Largs. Three years later, the Norwegians agreed to cede the Hebrides and the Isle of Man to Scotland, while the Scots recognized Norwegian rule over Shetland and Orkney. In 1472, Shetland and Orkney were annexed by Scotland after being used by King Christian I of Denmark as security for his daughter's dowry, which was never paid. This annexation ended the Norse presence in the British Isles, although the Norse settlers of the Northern Isles would assimilate into the Scottish population; by 2015, 29.9% of Shetlanders and 25.2% of Orcadians had Norse DNA. ²
Sources: ¹The Scotsman; ² Historica Wiki