Jethro is a figure from the Jewish Torah (the first five books of the Christian Old Testament): he is called a priest of Midian, and he becomes father-in-law to Moses.
Jethro, also known as "Reuel", is recorded as living in Midian, a territory stretching from east of the Dead Sea south onto the Sinai peninsula. He was likely a descendant of Abraham through Abraham's son named Midian. Jethro's daughter, Zipporah, becomes Moses's wife after Moses flees Egypt, having killed an Egyptian who was beating a Hebrew slave. Moses is said to have worked as a shepherd for Jethro for 40 years before returning to Egypt to lead the Hebrews to Canaan, the "promised land". What we know concerning Jethro is recorded in the book of Exodus.