Question: how uruk hai are born?
Answer: In the War of the Ring, the Uruk-hai made up a large part of Saruman's army, together with the Dunlendings, man-enemies of Rohan. There are suggestions that the Uruk-hai were the result of crossbreeding orcs and men. ... The Uruks of Saruman used an Elf-rune wrought in white metal on the front of their iron helms.