What did a medieval abbess earn?
1,166 pounds a year, the richest nunnery in England.
About $170,000 a month in today's gold.
A month of that pay weighs about as much as 3 footballs in gold.
"If the abbess of Shaftesbury married the abbot of Glastonbury, their heir would own more land than the king."
Where the money came from
Shaftesbury Abbey was said to have been founded by Alfred the Great around 888, with his daughter as its first abbess and a large gift of land. By 1086 the abbess also owned 111 houses in the town. Her income came from more than twenty manors, from Somerset to Sussex, and from parish churches and tithes. A saying ran that if the abbot of Glastonbury could marry the abbess of Shaftesbury, their heir would hold more land than the king. Like a great lord she owed the king seven knights for his army, and she had to keep boarders he sent her. Her lands entitled her to a seat in Parliament, but she was never summoned because she was a woman. In 1326 the bishop ruled that the house could support 120 nuns and no more. Even so it was often in debt, and once a bishop set each nun's allowance at 2 pence a week to save money. In 1527 the abbey gave the king £1,000 towards his claim to the French crown, ten times what Sherborne paid. The last abbess, Elizabeth Zouche, offered the king 500 marks to let her house stand. He refused, and in March 1539 she surrendered it with fifty-six nuns. Her pension was over £133 a year, more than forty-seven times the 56 shillings and 8 pence of the poorest sister.
Sources: british-history.ac.uk
What an abbess's pay bought in 1350
a hand-copied book: less than a day's pay
a craftsman's townhouse: 6 days' pay
a great stained-glass window: 4 weeks' pay
Harlech Castle: 12 years' pay, more than a whole year of it
the ransom of the King of France: 720 years' pay, more than a whole year of it
Every price of 1350, with its source, is on the prices page.