Elizabeth of Bar also known as Elisabeth (Isabel) de Bar-Pierrepont, was born circa 1345 at Hagestein, Zeeland, Netherlands. She was the youngest daughter of Theobald de Bar, Seigneur de Pierrepont and his wife Marie de Namur. When her father, Theobald, died between 2 August 1353 and 6 July 1354, and because he had no legitimate male heir, she became the heiress of Bar-Pierrepont. She married Otto, Lord of Arkel, son of John IV, Lord of Arkel and Irmengard of Cleves, somewhere before 18 October 1360. They had one son, John V, Lord of Arkel, born on September 11, 1362 in Gorinchem.