Marcomir was born in 0370 in Cologne. Marcomir's father was Clodius I and his mother was Blesinde d'Allemanie. His paternal grandfather was Dagobert; his maternal grandfather is Chlodome *. He had a brother and a sister, named Marcomir and Blesinde de Cologne. He was the oldest of the three children. He died at the age of 55 in 0425.