Udal law is a Norse derived legal system, which is found in Shetland and Orkney, Scotland and in Manx law in the Isle of Man. It is closely related to Odelsrett.
Udal law was codified by the kings Magnus I of Norway "the good" and Magnus VI of Norway "lawmender". The Treaty of Perth transferred the Outer Hebrides and Isle of Man to Scots law while Norse law and rule still applied for Shetland and Orkney.
Scottish Courts have intermittently acknowledged the supremacy of Udal law in property cases up to the present day. Major differences from Scots law include shore ownership rights, important for pipelines and cables.
Udal law generally holds sway in Shetland and Orkney, along with Scots law.
Not all land in Shetland and Orkney can be described as falling under udal tenure. The type of tenure depends on how the title arose:
The udal tenant held without charter by uninterrupted possession on payment to the Crown, the kirk, or a grantee from the Crown of a tribute called skat (Norwegian: skatt, now meaning "tax"), or without such payment, the latter right being more strictly the udal right. They were convertible into feus at the option of the udallers.Succession law had unique traits, as the eldest son inherited the father's main residence, while the rest of the property was shared among siblings, daughters inheriting half as much as sons.