King Edward IV granted Robert the office of Controller of the Scrutiny of good passing through the port of London in 1461, a potentially lucrative position.
[2] William's mother Elizabeth was the sister of Oliver King, eventual Secretary to Edward IV and Henry VII, and Bishop of Exeter.
[1][3] William's sister Elizabeth married Sir John Philpot (d. 1502) in 1488, with a dowry of 400 marks and land in Middlesex from her uncle, Oliver King.
Though Cosyn received and retired from several prebends, vicarages, and offices over the next thirty-seven years, he kept his position at Bedford Minor until his death in 1525.
[13] After three years as Bishop of Exeter, Pope Alexander VI issued a bull to translate King to the Diocese of Bath and Wells.
Cosyn obtained the Archdeaconry of Bath in 1497, the prebend of Ilton in October 1498, and finally the office of Dean of Wells Cathedral in December 1498.
Moving forward, Cosyn attempted to gain a greater understanding of his position as Dean, and work towards increasing his social standing on his own.
The main result of Cosyn's attempt to understand his Deanery and the lands he was responsible for, was the assembly of a collection of transcripts, statutes, customs, and records on the liberties, rents and procedures of Wells Cathedral in 1505.
[23] In the period between Bishop King's death and the end of Cosyn's tenure as Dean of Wells, members of the Catholic Church in central Europe suffered some of the most tumultuous years in the history of Western Christianity.
Henry VIII had his disputes with Luther over the sacraments, and William Tyndale was working on his translation of the New Testament into English, but little violence erupted because there was a general absence of religious division.
On 19 August 1510 Cosyn proposed that he would visit the College of chantry priests, likely to ensure that they performed their assigned duties, such as masses for the dead.
The election became a lawsuit that dragged on for two years, and only ended when the Archbishop of Canterbury, William Warham arbitrated the case, and appointed Caveley as Vicar.
[27] The most significant dispute was over Cosyn's attempt to gain a Papal Dispensation that would allow him to receive the First Fruits of his position, without remaining resident for the required eight months each year.
[36] In his will, Cosyn reserved funds for twenty poor men to bear torches for his funeral, and forgave the debt of £40 of one Richard Baker.