|Robert Grosseteste in a 14th century volume of his works|
We are sure he is the Robert Grosseteste who was appointed to the diocese of Lincoln in 1225 and concurrently as archdeacon of Leicester in 1229. The double-duties apparently made him ill within a few years, and he pared down to the position of canon in Lincoln Cathedral, and started lecturing in theology at Oxford on the side. According to Thomas of Eccleston, Franciscan chronicler for the years 1224-1258, Grosseteste joined the Franciscan school at Oxford around 1230.
Association with Oxford and reduced ecclesiastical responsibilities allowed him time for scientific theorizing and writing.
He began producing texts on the liberal arts, and mainly on astronomy and cosmology. His most famous scientific text, De luce (Concerning Light), argued that light was the basis of all matter, and his account of creation devotes a great deal of space to [...] God’s command, ‘Let there be light.’ Light also played a significant role [in] his epistemology, as he followed the teachings of St. Augustine that the human intellect comes to know truth through illumination by divine light. Grosseteste’s interest in the natural world was further developed by his study of geometry, and he is one of the first western thinkers to argue that natural phenomenon can be described mathematically. [source]
|From De Sphera, on astronomy|
There are 120 works attributed with confidence to him. They have not all been translated and examined yet. Focus has been on his theological and philosophical works, but many writings still exist only in manuscript form. His still-unedited scientific works may reinforce the current belief that he proves that pre-Renaissance scientific progress was further advanced than previously thought.
He died on 8 October, 1253, and was buried in a memorial chapel in Lincoln Cathedral.
Postscript: If you are curious in his Latin texts, seek here.