Ser Mark Osgrey was the head of House Osgrey and a talented swordsman and jouster during the reign of six Baratheon Kings. He saw peace under King Trystane Baratheon's reign, combat in the War of the Split Stag, and won dozens of tourneys during his lifetime. He was born in 413 AC and lived well into old age.
Ser Mark Osgrey attended the Tourney of Longtable at the age of three and seventy.
"Better men than you rot dead in the ground despite their prowess. Ser Mark Osgrey, The Grey Knight, Quenton Drox, all swordsmen the likes of which we shall not see again. All good men, and now all dead." - Loren Lannister