Mariamne I (died 29 BCE), also called Mariamne the Hasmonean, was a Hasmonean princess and the second wife of Herod the Great. She was known for her great beauty, as was her brother Aristobulus III. Herod's fear of his rivals, the Hasmoneans, led him executing all of the prominent members of the family, including Mariamne.
Her name is spelled Μαριάμη (Mariame) by Josephus, but in some editions of his work the second m is doubled (Mariamme). In later copies of those editions the spelling was dissimilated to its now most common form, Mariamne. In Hebrew, Mariamne is known as מִרְיָם, (Miriam), as in the traditional, Biblical name (see Miriam, the sister of Moses and Aaron).
Mariamne was the daughter of the Hasmonean Alexandros, also known as Alexander of Judaea, and thus one of the last heirs to the Hasmonean dynasty of Judea. Mariamne's only sibling was Aristobulus III. Her father, Alexander of Judaea, the son of Aristobulus II, married his cousin Alexandra, daughter of his uncle Hyrcanus II, in order to cement the line of inheritance from Hyrcanus and Aristobulus, but the inheritance soon continued the blood feud of previous generations, and eventually led to the downfall of the Hasmonean line. By virtue of her parents' union, Mariamne claimed Hasmonean royalty on both sides of her family lineage.
Her mother, Alexandra, arranged for her betrothal to Herod in 41 BCE. The two were wed four years later in Samaria. Mariamne bore Herod four children: two sons, Alexandros and Aristobulus (both executed in 7 BCE), and two daughters, Salampsio and Cypros.