Atreus.

 Atreus (Ἀτρεύς) was a king of Mycenae. His parents were Pelops and Hippodamia. Also, Atreus was known as father of Agamemnon and Menelaus. His wife was Aerope. His brother was Thyestes.

King ruled Mycenae in the Peloponnese. Eurystheus was his predecessor. Agamemnon was his successor.

In Greek mythology Atreus met with different characters, such as: Helios, Aegisthus, and etc.

There is Treasury of Atreus on Panagitsa Hill at Mycenae, Greece.

Menelaus.

 Menelaus (Μενέλαος) was known as king of Mycena and husband of beautiful Helen. His parents were Atreus (Ἀτρεύς) and Aerope (Ἀερόπη). Menelaus had an elder brother named Agamemnon. He was a king of Mycenae, too.

His wife Helen of Troy was kidnapped by Theseus and Pirithous, when she was a child.

Menelaus was an important character in the Trojan War.

He and his spouse Helen of Sparta had a daughter Hermione.