[5] Olave Sinclair is said to have been blind in one eye, the result of leaping from Sumburgh Head to escape a band of marauders from the Isle of Lewis.
[6] A version of the story explains that Sinclair had a quarrel with William MacLeod of Lewis, whose wife had brought him lands in Shetland.
A letter in the Scots language confirming his appointment on 12 December 1561, calls him the "chamberlane and bailye of oure lordschip and landis of Yeitland, baith maineland and ilis".
[13][14] As foud, Sinclair collected feudal rents in money and farm produce due to the Scottish crown and sent them to Edinburgh.
[15] Rents typically included dairy produce, and the butter, known as the "fat goods" was barrelled in Kirkwall on Orkney and shipped to Leith.
In December 1566, during an entertainment written by George Buchanan for the baptism of James VI at Stirling Castle, Latin verses were sung by nymphs and satyrs in honour of the food and hosts, and characters represented the Orkney Islands.
[22] In July 1567, the Privy Council of Scotland asked Sinclair, as a "receiver" of rents, to submit an account for the queen's income in previous years and come to Edinburgh to show it to the lords and auditors of the Scottish exchequer.
[26] Sinclair's official work included writing licences and testimonials in favour of Hanse merchant skippers like Johan Kordes of Bremen who was given a permit to use the haven of Baltasound in 1560.
In August 1563, Sinclair wrote to the burgomaster and town council of Bremen about Kordes and his unlicensed competitors, who were exhausting the island resources.
[27][28][29] In September 1567, Sinclair prepared a testimonial for Gerdt Hemeling of Bremen whose ship and cargo of salted fish had been taken from his trading base at "Drosteness" by the Earl of Bothwell, who was briefly Duke of Orkney.
[30] A Scottish chronicle, the Diurnal of Occurrents mentions that Bothwell had dinner with Sinclair in Shetland in August 1567 after his flight from the battle of Carberry Hill.
[32] In January 1568, Bothwell wrote of his meeting with the Bremen skipper Gerdt Hemeling at Sinclair the receiver's house on Unst.