Thirlage

Thirlage was a feudal servitude (or astriction) under Scots law restricting manorial tenants in the milling of their grain for personal or other uses. Vassals in a feudal barony were thirled to their local mill owned by the feudal superior. People so thirled were called suckeners and were obliged to pay customary dues for use of the mill and help maintain it.

The term thirlage is a metathesis of Scots thrillage ‘thralldom’, derived from thril ‘thrall’, which was a body servant, retainer, or vassal to a noble or chief. The term is interchangeable with Scots carl (or English churl) and indicates subservience to the feudal superior and feudal laws; the situation being not that far removed from the conditions of slavery.

The obligations of thirlage eventually ceased to apply, but thirlage in Scotland was only formally and totally abolished on 28 November (Martinmas) 2004 by the Abolition of Feudal Tenure etc. (Scotland) Act 2000.

An identical feudal astriction existed and was enforced actively in feudal western Europe, e.g. mill soke in England,banalité du moulin in France, banmolen in the Netherlands, Mühlenzwang in Germany.

Thirlage was the feudal law by which the laird (superior) could force all those vassals living on his lands to bring their grain to his mill to be ground. The law ensured that all the grain the vassals produced could be measured and thus taxed. Vassals had to carry out repairs on the mill, maintaining the lade and weir as well as conveying new millstones to the site. Such trees as beech and particularly hornbeam were grown as a crop to provide the necessary wood for the mill machinery.

The Thirlage Act was repealed in 1779 and after this many mills fell out of use as competition and unsubsidised running costs took their toll. This explains why so many mills ceased to be marked on maps after this date. Lambroch Mill for example was on the Annick Water near Stewarton in Ayrshire and apart from the weir and some other indications, it has entirely vanished, most likely because it was the thirlage mill for Lambroughton and its business went to Lainshaw or Cunninghamhead mill after the thirlage act was repealed.

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